Paramedic Drugs UK

Question 1

Adrenaline:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 1

Dose / Route:

1: 1000 = 500 mcg IM
1: 10,000 = 1mg IV/IO given as a rapid bolus

Indicated:

1: 1000 = Anaphylaxis, Life threatening asthma.
1: 10,000 = Cardiac arrest

Contraindicated:
Do not give repeated doses in hypothermic patients.

Cautions:
Severe HTN in patients on non-cardioselective beta blockers.

Question 2

Adrenaline:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 2

Actions:
Catecholamine, non-selective sympathomimetic.

Agonises Alpha- & Beta-Adrenoreceptors in the cardiac, pulmonary and blood vessel tissue, leading to tachycardia, bronchodilation & vasoconstriction.

Alpha-adrenoreceptor stimulus increases peripheral resistance, resulting in increased myocardial and cerebral blood flow during CPR.

Beta-1 adrenoreceptor agonist, and so is a positive inotrope (increased contractility), chronotrope (increased frequency of SA node depolarisation) and dromotrope (increased conduction through AV node).

Beta-2 adrenoreceptor stimulus causes smooth muscle relaxation, notably in the lungs, causing subsequent bronchodilation, consequently improving ventilation and aiding oxygenation. Also, a histamine antagonist.

A - Parenteral D- Plasma Proteins M – Liver E- urine

Question 3

Amiodarone:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 3

Dose / Route:
300 mg, 150 mg IV/IO.
Given as a rapid bolus into a large vein, and well flushed.

Indicated:
Shockable rhythm following 3rd/5th unsuccessful defibrillation attempts.

Contraindicated:
None

Side effects:
Bradycardia, Vasodilation causing Hypotension, Bronchospasm, Arrhythmias – Torsardes de pointes

Question 4

Amiodarone:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 4

Actions:
Class III Anti-arrhythmic (although displays characteristics of all 4 classes).
Non-competitive Alpha and Beta-adrenergic inhibitor.

Acts on the myocardium, nodal and connective tissues, delaying the efflux of K+ from the cell by blocking K+ channels, prolonging the refractory period of depolarisation. Also blocks sodium channels at rapid pacing frequencies.

Prolonging plateau phase (phase 3) of the cardiac action potential, refractory period (via Na/K channels) and slows AV conduction (Na channel)

Shows beta blocker-like and calcium channel blocker-like actions on the SA and AV nodes, depressing their automaticity.

A – Parenteral D – Plasma Proteins, widespread, esp. liver & adipose tissue M – Liver, bile E - Faeces

Question 5

Aspirin:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 5

Dose / Route:
300 mg PO

Indicated:
Clinical or ECG evidence suggestive of myocardial ischaemia or infarction.

Contraindicated:
Known allergy/hypersensitivity, Active GI bleed, Haemophilia or other known clotting disorders, <16 years old, Severe hepatic disease.

Cautions:
Single 300 mg dose means benefits outweigh risks for most cautions, including asthma, pregnancy, kidney/liver failure, gastric/duodenal ulcer, current treatment with anticoagulants.

Side effects: GI bleeding, Wheezing in some asthmatics (Due to NSAID properties).

Question 6

Aspirin:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 6

Actions:
Anti-platelet.

Directly and irreversibly inhibits the enzyme cyclo-oxygenase (COX1 and COX2), preventing arachidonic acid being synthesised into the eicosanoids thromboxanes and prostaglandins.
The aggregation agent Thromboxane A2 (TXA2) is released by activated platelets, causing platelet aggregation in the clotting process, and thereby inhibition prevents platelet plugs from growing, or new ones forming.

Aspirin may also prevent the synthesis of platelet aggregation inhibitor prostacyclin.

COX inhibition also prevents the production of inflammatory prostaglandins that would otherwise go on to cause pain, swelling and inflammation.

Aspirin’s inhibition of COX can cause unwanted GI side effects, due to COX being involved in the production of protective gastrointestinal secretions.

A – Enteral D – Plasma Proteins M – Liver E - Urine

Question 7

Atropine Sulphate:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 7

Dose / Route:
600 mcg IV/IO, delivered as a rapid bolus.

Indicated:
symptomatic bradycardia in the presence of:
Absolute bradycardia; hypotension; paroxysmal ventricular arrhythmias requiring suppression; inadequate perfusion causing confusion etc; bradycardia following ROSC.

Contraindicated:
Should not be given to treat bradycardia in suspected hypothermia.

Side effects:
Dry mouth, Visual blurring, Pupil dilation. Confusion/hallucinations. Tachycardia. Small dose / Slow administration may cause paradoxical bradycardia.
In older people, retention of urine may occur.

Question 8

Atropine Sulphate:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 8

Actions:
Anti-cholinergic.

Acts as a competitive antagonist at cholinergic receptors (specifically at muscarinic acetylcholine receptors M1-M5, non-selectively), inhibiting stimulation from parasympathetic nerve fibres (such as the vagus nerve) by blocking the effects of the neurotransmitter acetylcholine and allowing a more dominant sympathetic response.

Also causes increased velocity of conduction through the AV node, potentially correcting 2nd and 3rd degree AV conduction blocks, particularly those induced by digitalis toxicity.

A – Parenteral D – Plasma Proteins M – Liver E - Urine

Question 9

Benzylpenicillin:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 9

Dose / Route:
1.2 g IV/IO/IM (600mg powder diluted with 19.2ml (20ml) or 3.2ml (4ml) WFI). Slow injection.

Indicated:
Suspected Meningococcal Septicaemia with non-blanching rash and signs & symptoms suggestive of meningococcal septicaemia.

Contraindicated:
Severe Penicillin allergy (more than a simple rash alone).

Question 10

Benzylpenicillin:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 10

Actions:
Broad spectrum Abx.

Acts against gram-positive and gram-negative bacteria, binding to Penicillin binding proteins and inhibiting bacterial wall synthesis, making the cell wall osmotically unstable.
Cell lysis is then mediated by bacterial cell wall autolytic enzymes, destroying the cell wall and causing bacterial death.

A – Parenteral D – Plasma Proteins M – Small amount by bile, largely unchanged E - Urine

Question 11

Chlorphenamine:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 11

Dose / Route:
10 mg IV/IO/IM (slowly, over a minute).

Indicated: 
Anaphylactic reactions (following IM ADR), Symptomatic allergic reactions.

Contraindicated:
Known hypersensitivity. Children <1 year of age.

Cautions:
Hypotension. Epilepsy. Glaucoma. Hepatic disease. Prostatic disease

Side effects:
Sedation. Dry mouth. Headache. Blurred vision. Psychomotor impairment. Gastrointestinal disturbance. Transient hypotension. Convulsions (rare).

Older people are more likely to suffer side effects. Warn patients against driving/complex psychomotor tasks.

Question 12

Chlorphenamine:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 12

Actions:
Anti-histamine.

Competitive non-selective antagonist for central and peripheral H1-receptors.
Blocks effects of histamine, leading to temporary relief of negative symptoms, such as swelling, sneezing and diarrhoea.

Crosses the blood-brain barrier easily, and so causes sedation/drowsiness side effects.

A – Parenteral D – Plasma Proteins M – Liver E - Urine

Question 13

Clopidogrel:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 13

Dose / Route:
300 mg (thrombolysis) or 600mg (PPCI), given PO (75mg or 300mg tablets).

Indicated:
STEMI and: not already on CLO, Anticipated PPCI, or receiving/anticipated thrombolysis.

Contraindicated:
Active pathological bleed (Peptic ulcer, Intracranial haemorrhage). Known allergy or hypersensitivity. Severe liver impairment.

Cautions:
300 mg dose means benefits outweigh risks for most cautions; pregnancy, NSAIDs, renal impairment.

Side effects:
Dyspepsia, Abdominal pain, Diarrhoea. Haemorrhage (GI or intracranial).

Question 14

Clopidogrel:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 14

Actions:
Anti-platelet.

ADP selective antagonist. Irreversibly prevents ADP binding to platelet receptors and impairs the ADP-mediated activation of the fibrinogen binding protein complex, glycoprotein GPIIb/IIIa, and so inhibiting further platelet activation/aggregation and fibrin crosslinking.

A – Enteral D – Plasma Proteins M – Liver E - Urine

Question 15

Dexamethasone:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 15

Dose / Route:
18 mths – 6 years = 3.8 mg
1 mth – 12mths = 1.9 mg PO

Indicated:
Mild/Moderate/Severe/Life threatening croup in children aged 1 month to 8 years.

Contraindicated:
Diagnosed HTN. Systemic infection / Sepsis. Immunocompromised. Hypersensitivity.

Cautions:
Could further worsen upper airway by distressing the child

Side effects:
Increased susceptibility to infection. Dyspepsia. Mood changes. Malaise.

Question 16

Dexamethasone:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 16

Actions:
Corticosteroid. Reduces subglottic inflammation.

Glucocorticoid receptor agonist, which crosses cell membranes and binds with high affinity to specific cytoplasmic glucocorticoid receptors.

Inhibits leukocyte infiltration, suppressing humoral immune response. Reduces cytokine production, inhibiting prostaglandin synthesis, reducing inflammation.

The anti-inflammatory actions of dexamethasone are thought to involve phospholipase A2 inhibitory proteins, lipocortins, which control the synthesis of mediators of inflammation such as prostaglandins and leukotrienes.

A – Enteral D – Plasma Proteins M – Liver E - Urine

Question 17

Diazepam:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 17

Dose / Route:
10 mg IV/IO/PR. IV given over 2 minutes (3-5 in children)

Indicated:
Prolonged (>5 min) or repeated (3 or more in 60 minutes) convulsions, who are CURRENTLY CONVULSING (convulsion not secondary to hypoxia or hypoglycaemia).
Eclamptic seizures lasting over 2-3 minutes or if it is recurrent. Symptomatic cocaine toxicity (severe hypertension, chest pain or convulsion).

Contraindicated:
Known hypersensitivity.

Cautions:
Side effects are more likely if alcohol, antidepressants or CNS depressants have been taken.
Doses given by parents / carers should be taken into account when calculating maximum cumulative dose.

Side effects:
Respiratory depression. Hypotension (consider removing patient flat or allowing a 10 minute recovery period prior to removal). Sedation.
Amnesia/Lightheadedness/drowsiness/confusion/unsteadiness.

Question 18

Diazepam:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 18

Actions:
Benzodiazepine.

Benzodiazepine binding site agonist, which acts on the membranes of the cells in the post-synaptic cleft.
By attaching to the benzodiazepine binding site of GABA receptors on ligand gated Cl- channels, diazepam potentiates the effect of the neurotransmitter GABA (Gamma Amino Butyric Acid) in binding to GABA-A receptors, by increasing the affinity of the receptor for GABA.
In doing so, the chloride channel opens, causing an influx of Cl- ions into the cell, hyperpolarising the membrane. This causes the resting potential of the membrane to be increased, and so a greater voltage stimulus from the synapse is required to cause the membrane to reach it’s action potential and depolarise, and hence this occurs less frequently.

This reduced excitability results in a reduced frequency of impulses through the post synaptic neurons, causing a sedative and anticonvulsant effect.

Cl- ion channels are located alongside Ethanol ion channels, hence diazepam has an increased sedative effect in presence of alcohol

A – Parenteral/Enteral D – Plasma Proteins M – Liver E – unchanged in urine

Question 19

Entonox:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 19

Dose / Route:
PRN Inhaled

Indicated:
Moderate to severe pain, Labour pain

Contraindicated: 
Decompression sickness (anyone who has been diving in the past 24 hours). Severe head injury with impaired consciousness. Violently disturbed psychiatric patients. Intraocular injection of gas within 4 weeks. Abdominal pain where intestinal obstruction is suspected.

Cautions:
Any risk of pneumothorax, pneumomediastinum or pneumoperitoneum.

Question 20

Entonox:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 20

Actions;
Dissociative analgesia.

Rapidly diffuses through the alveoli into the bloodstream. Nitrous oxide induces opioid peptide release in brainstem, leading to activation of descending noradrenergic neurones, modulating the nociceptive process in the spinal cord.

Due to its insolubility in blood, Entonox maintains a high partial pressure within the blood, and will readily diffuse into any potential space, which can have a deleterious effect if used with patients with air-containing spaces such as a pneumothorax, pneumomediastinum or pneumoperiotenium.

A – Inhaled D – Plasma Proteins M – Blood insoluble, not metabolised E – expiration

Question 21

Furosemide:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 21

Dose / Route:
40 mg in 4ml IV.

Indicated:
Pulmonary oedema secondary to LVF.

Contraindicated:
Reduced GCS with liver cirrhosis. Cardiogenic shock. Severe renal impairment with anuria. <18 YOA.

Cautions:
Hypokalaemia, Pregnancy, Hypotensive.

Side effects:
Hypotension, Gastrointestinal disturbances.

Question 22

Furosemide:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 22

Actions:
Loop diuretic.

Competitive inhibitor at chloride binding site on Na, K, Cl cotransporter, in the thick ascending limb of the Loop of Henle, which inhibits sodium reabsorption. Lumen becomes hypertonic, decreasing osmotic gradient throughout nephron and reduced water reabsorption, leading to increased urine output. (Ascending loop responsible for 25% reabsorption of Na, so is a very potent diuretic).

Also causes vasodilation by inhibition of vasopressors, increasing the vascular space, resulting in increased peripheral pooling, and subsequent reduction in preload and afterload.

A – Parenteral D – Plasma Proteins M – Liver E - Urine

Question 23

Glucagon:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 23

Dose / Route:
1 mg IM.

Indicated:
Hypoglycaemia, where oral glucose is not possible or patient is unconscious.

Contraindicated:
Low glycogen stores (Recent GLU use), Pheochromocytoma. Not to be given IV (increased chance of vomiting).

Cautions:
Avoid IM where thrombolysis is likely.

Side effects: Nausea, Vomiting, Hypokalaemia, Hypotension.

Question 24

Glucagon:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 24

Actions:
Synthetic polypeptide hormone.

Binds to glucagon receptors in the Liver, stimulates liver to convert glycogen stores into glucose to increase blood sugar.

A – Parenteral D – Plasma Proteins M – Liver E - Urine

Question 25

Glucose 10%:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 25

Dose / Route:
10 g IV/IO (Max – 30 g).

Indicated:
Hypoglycaemia, where oral glucose is not possible. Unconscious patient where hypoglycaemia is considered a likely cause. Management of hypoglycaemia in patients who have not responded to IM glucagon after 10 minutes

Contraindicated:
Not to be give IM or subcutaneously.

Cautions:
Administer via large cannula in large vein, flush well to avoid vein irritation from residual glucose.

Question 26

Glucose 10%:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 26

Actions:

Increases intravascular blood glucose levels to combat hypoglycaemia.

A – Parenteral D – Plasma Proteins M – Tissues & liver E - Urine

Question 27

Glucose 40% gel:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 27

Dose / Route:
10 g PO.

Indicated:
Hypoglycaemia in the conscious patient with no risk of choking or aspiration.

Contraindicated:
None.

Side Effects:
None.

Cautions:
Altered consciousness. Can be used to soak a gauze swab, placed between patient’s lip and gum.

Question 28

Glucose 40% gel:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 28

Actions:
Increase in blood glucose via absorption through the buccal route.

A – Enteral D – Plasma Proteins M – rapidly in the Liver & tissue to CO2 and H2O E - Urine

Question 29

Glyceryl trinitrate – Nitrate:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 29

Dose / Route:
400mcg Buccal.

Indicated:
Cardiac chest pain from Angina or MI with a systolic BP of >90mmHg.
Breathlessness due to pulmonary oedema in acute heart failure with a systolic BP of >110mmHg.
Suspected cocaine toxicity presenting with chest pain.

Contraindicated:
Unconscious. Hypotension (<90mmHg in angina/MI, <110mmHg in heart failure). Head trauma. Hypovolaemia. Cerebral haemorrhage. Sildenafil (Viagra) use in <24 hrs.

Side effects:
Headache, Dizziness, Hypotension

Question 30

Glyceryl trinitrate – Nitrate:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 30

Actions:
Nitrate.
Absorbed through buccal route, GTN is denitrated to Nitric Oxide, which activates guanylate cyclase which stimulates production of cGMP, which in turn acts on myosin-2 in smooth muscle of the vascular endothelium.

The subsequent release of calcium ions causes them to relax, resulting in vasodilation of coronary arteries and systemic veins, and therefore reduced peripheral resistance (reduced preload, afterload, BP and coronary spasm).

A – Sublingual D – Plasma Proteins M – Liver E - Urine

Question 31

Heparin:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 31

Dose / Route:
5,000 units IV with Reteplase
4,000 units <67 kg OR 5,000 units >67 kg IV with Tenecteplase.
Additional 1,000 units if HEP bolus not within 45 min of RET or TEN bolus.

Indications: STEMI in conjunction with Reteplase or Tenecteplase, to prevent re-infarct.

Contraindications:
Haemophilia, Thrombocytopenia, Recent cerebral haemorrhage, Severe HTN, Severe liver disease, Oesophageal varices, Peptic ulcer, Major trauma, Recent eye / Neuro surgery, Acute bacterial endocarditis, Spinal / Epidural anaesthesia.

Side effects:
Haemorrhage.

Question 32

Heparin:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 32

Actions:
Anti-coagulant.
Reversibly binds to Anti-Thrombin III, inactivating clotting factors (particularly thrombin and factor Xa) and plasmin.
Accelerates the rate of neutralising coagulation factors by antithrombin.
Prevents the progression of existing clots by inhibiting further clotting.

A – Parenteral/Enteral. D – Plasma Proteins.
M – Liver. E - Urine

Question 33

Hydrocortisone:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 33

Dose/Route:
Asthma / Adrenal crisis = 100 mg IV/IM. (2ml WFI).
Anaphylaxis = 200 mg IV/IM, Given slowly over 2 minutes.

Indicated:
Severe/Life threatening asthma, Anaphylaxis, Adrenal crisis.

Contra-indicated:
Known allergy to product or excipients.

Cautions:
Avoid IM if thrombolysis likely.

Side effects:
Burning or itching if administered quickly, due to phosphate preservative.

Question 34

Hydrocortisone:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 34

Actions:
Glucocorticosteroid.
Binds to cytosolic glucocorticoid receptors in cell cytoplasm. The newly formed receptor-ligand complex induces lipocortin synthesis which inhibits inflammatory effects, by supressing phospholipase-A2 and therefore production of arachidonic acid, and supressing cyclooxygenase and therefore reducing prostaglandins and leukotrienes production.

Hydrocortisone also has an antihistamine effect, by stabilising mast cell membranes, inhibiting mast cell degranulation and thereby reducing histamine release.

Glucocorticoid that suppresses cell mediated immunity, specifically by inhibiting the genes that code for cytokines (IL-2), Reduced cytokine production limits T cell proliferation. Also suppress humoral immunity, reducing B cell expression.

A – Parenteral. D – Plasma Proteins. M – Liver, also by most tissues. E – Urine.

Question 35

Ibuprofen:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 35

Dose/Route:
400 mg PO.

Indications:
Mild to moderate pain and/or pyrexia, Soft tissue injuries.

Contraindications:
Dehydrated. Hypovolaemic. Renal insufficiency. Active upper GI disturbance. Pregnant. Other NSAIDs taken in last 4 hours.

Cautions:
Wheezing in some asthmatics, >65 YOA who have not recently used NSAIDs.

Side effects:
Nausea, Vomiting, Tinnitus.

Question 36

Ibuprofen:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 36

Actions:
NSAID.
Non-selective COX Inhibitor, inhibits synthesis of Prostaglandin H2 (PGH2) from Arachidonic acid.
PGH2 is converted into Prostaglandins which then produce Pain, Inflammation and Heat, and so inhibition of this eases these symptoms.

Main activity from ibuprofen appears to come from inhibiting COX2 – responsible for synthesis of the prostaglandins that cause heat / swelling / pain.

Anti-pyretic properties due to action on the hypothalamus – vasodilation leads to increased peripheral blood flow and greater heat dissipation.

Inhibition of COX 1 causes increased production of HCl- in stomach and decreases mucous production, which can cause the side effect of stomach ulcers with ibuprofen treatment.

A – Enteral. D – Plasma Proteins. M – Liver. E - Urine.

Question 37

Ipratropium Bromide:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 37

Dose / Route:
500mcg in 2ml or 250mcg in 1ml NEB.

Indicated:
Acute severe / life threatening asthma, Asthma unresponsive to SLB, Exacerbation of COPD unresponsive to SLB.

Contraindicated:
None.

Cautions:
Glaucoma. Pregnancy/breastfeeding. Prostatic hyperplasia. In COPD patients, limit nebulisation to 6 mins.

Side effects:
Nausea, Dry mouth, Tachycardia / Arrhythmia, Paroxysmal tightness of the chest, Allergic reaction.

Question 38

Ipratropium Bromide:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 38

Actions:
Anti-muscarinic bronchodilator.

Ipratropium bromide is an anti-cholinergenic, and inhibits acetylcholine, and therefore parasympathetic activity.
Inhibiting acetylcholine at muscarinic cholinergic receptors decreases contractility of smooth muscle in the small airways, causing bronchodilation, and improving ventilation and oxygenation.
Acetylcholine blocking also reduces secretion formation and increases cilia activity to help shift excess mucous.

Depressing the parasympathetic response gives a more dominant Sympathetic response.

A – Inhaled. D – Plasma Proteins. M – E – unchanged in Faeces.

Question 39

Metoclopramide:

1. Dose/Route?
2. Indication?
3. Contr-indications?
4. Cautions?

Answer 39

Dose/Route:
10 mg in 2ml IV/IM.

Indicated:
Nausea/vomiting in adults aged 20+. Opiate induced nausea + vomiting.

Contraindicated:
<20 YOA. Renal failure. Phaeochromocytoma. Gastric obstruction. Perforation / Haemorrhage / 3-4 days after GI surgery. Drug overdose.

Cautions:
Avoid IM where thrombolysis likely.

Side effects: Drowsiness/restlessness. Cardiac conduction abnormalities. Diarrhoea. Rash.

Question 40

Metoclopramide:
Actions &
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 40

Actions:

Anti-emetic.
Dopamine D2 antagonist, which raises trigger threshold of the Chemoreceptor trigger zone, in the medulla oblongata (the CTZ, when stimulated, sends messages to another area of the brain, the vomiting centre, which in turn sends messages to the stomach to initiate the vomiting reflex).

Inhibits gastric smooth muscle relaxation. Reduced oesophageal reflux by increasing tightness of cardiac sphincter and relaxation of the pyloric sphincter, causing accelerates gastric emptying.
Increased peristalsis of the duodenum and the jejunum accelerates intestinal transit. These actions physically prevent vomiting.

Also antagonises 5-HT3 receptors in higher doses.

A – Parenteral. D – Plasma Proteins M – Liver. E - Urine.

Question 41

Midazolam:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 41

Dose/Route:
Seizures: 2 mg IV (2mg/2ml ampoule) or 10 mg Buccal (5mg/1ml solution).
Sedation: 0.5-1mg IV

Indicated:
Convulsion lasting >5 minutes, >3 focal seizures in 1 hour, Convulsion continuing 10 minutes after first dose of medication, TBI with agitation.

Contraindicated:
None.

Cautions:
Rapid bolus may cause Respiratory depression, <6 YOA at risk of drug accumulation due to hepatic immaturity, Enhanced sedative effects where alcohol / sedative drugs present.

Side effects:
Respiratory depression, Hypotension,

Question 42

Midazolam:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 42

Actions:

Benzodiazepine derivative.
In the same mechanism of action as diazepam, midazolam is a benzodiazepine receptor agonist, which acts on the membranes of the cells in the post-synaptic cleft.
By attaching to the benzodiazepine receptors on ligand gated Cl- channels, diazepam increases the effect of the neurotransmitter GABA (Gamma Amino Butyric Acid) in binding to GABA-A receptors. In doing so, the chloride channel opens, causing an influx of Cl- ions into the cell, hyperpolarising the membrane.
This causes the resting potential of the membrane to be increased, and so a greater voltage stimulus from the synapse is required to cause the membrane to reach it’s action potential and depolarise, and hence this occurs less frequently.
This reduced excitability results in a reduced frequency of impulses through the post synaptic neurons, causing a sedative and anticonvulsant effect.

Cl- ion channels are located alongside Ethanol ion channels, hence midazolam has an increased sedative effect in presence of alcohol.

A – Parenteral/Enteral. D – Plasma Proteins. M – Liver. E – unchanged in urine.

Comparison with Diazepam:
More potent (2-5 times more), requires a smaller dose. Lower bioavailability when given PO due to first pass metabolism. Much shorter half life. Faster elimination time. More consistent anterograde amnesia during moderate sedation.

Question 43

Misoprostol:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 43

Dose / Route: 
600 mcg (3x 200mcg tablet) PO . 
800mcg PR (4 x 200mcg tablets).

Indicated:
PPH <24 hrs of labour (uncontrollable by uterine massage).
Miscarriage with life threatening bleeding and confirmed diagnosis, Where SYN or OCT inappropriate (e.g. HTN >140/90) or have been ineffective after 15 minutes.

Contraindicated:
Allergy.
Active labour.
Possible multiple pregnancy/foetus in utero.

Side effects:
Abdominal pain, Nausea, Vomiting, Diarrhoea, Pyrexia, Shivering.

Question 44

Misoprostol:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 44

Actions:
Prostaglandin analogue uterotonic drug.

Binds to prostanoid receptors on myometrial cells to increase amplitude and frequency of uterine contraction which in turn compresses blood vessels to stem blood loss.

Eliminated: breast milk

Question 45

Morphine Sulphate:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 45

Dose / Route:
10 mg IV/IM (Max = 20mg).
20mg oral.

Indicated:
Moderate to severe pain.
AMI pain.

Contraindicated:
<1 YOA, Respiratory depression, Hypotension, Head injury (GCS <9), Allergy, Severe headache.

Cautions:
Severe renal / hepatic impairment.
Pregnancy. Chest injury.
Respiratory problems e.g. asthma or COPD.
Head injury. Acute alcohol intoxication. Medication (Antidepressants, Sedatives, Tranquillisers).

Side effects:
Respiratory depression. Cardiovascular depression. Nausea. Vomiting. Drowsiness. Pupillary constriction.

Question 46

Morphine Sulphate:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 46

Actions:
Centrally acting opioid analgesic.

Inhibition of nociceptor impulse transmission at synapses is achieved by morphine binding to opiate receptors on ligand gated potassium channels on cell membranes in the CNS (predominantly the mu, kappa and delta receptors), causing them to open.
Increasing efflux of K+ ions out of the cell creates a hyperpolarised membrane.
This causes a greater voltage stimulus from the neurotransmitters across the synapse to be required to cause the membrane to reach its action potential and depolarise, and hence this occurs less frequently. This reduced excitability results in a reduced frequency of impulses through the post synaptic nociceptors, and hence a reduction in the perception of pain.

Opioids inhibit the pain signal at multiple steps in the nociception pathway (between primary and secondary neurons, and secondary and tertiary neurons) and can even decrease the emotional response to pain.

Also inhibits GABA inhibitory inter-neurons, allowing inhibition of descending pain pathway.

Histamine can be released following administration leading to vasodilation, bronchoconstriction and urticaria.

Respiratory depression occurs due to reduced responsiveness of respiratory control centre in the medulla oblongata to increases in CO2 and electrical stimulation.

A – Parenteral/Enteral (rapid).
D – Plasma Proteins. M – Liver. E – Urine.

Question 47

Naloxone Hydrochloride:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 47

Dose / Route:
400 mcg in 1 ml IM/IV/IO (Max = 4400mcg).

Indicated:
Reversal of acute opioid or opiate toxicity for respiratory arrest or respiratory depression. Unconsciousness & respiratory depression of unknown cause where opiate overdose is a possibility.
High-potency veterinary/anaesthetic preparation exposure, where consciousness is impaired or exposure was in the past 10 minutes.

Contraindicated:
Neonates born to opiate addicted mothers (serious withdrawal effects).

Side effects:
In patients who are physically dependent on opioids, naloxone may precipitate violent withdrawal symptoms, including cardiac arrhythmia.
Keep these patients in a groggy state with regular cardiac/respiratory reassessment.
Vomiting is a common side effect following naloxone administration - ensure access to suction.

Question 48

Naloxone Hydrochloride:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 48

Actions:
Competitive opioid antagonist.

Competitive opioid receptor antagonist for mu, kappa and sigma opioid receptor sites in the CNS. With a high affinity to opioid receptors, naloxone displaces opioids, and reverse their effects (such as respiratory depression, sedation, hypotension, etc).

This may, however, cause acute withdrawal in a patient who is dependant on opiates. The half life of naloxone hydrochloride is short, and so there is the potential for relapse into overdose once the effects of naloxone have worn off.

A – parenteral (rapid). D – Plasma Proteins.
M – Liver. E - Urine.

Question 49

Ondansetron:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 49

Dose / Route:
4 mg IM/IV given over 2 minutes.

Indicated:
Opiate induced nausea & vomiting. Treatment of nausea & vomiting.
Travel associated nausea & vomiting.

Contraindicated:
<1 month.
Known sensitivity to ondansetron.

Cautions:
QT interval prolongation.
Hepatic impairment.
Pregnancy. Breastfeeding.

Side effects:
Hiccups. Constipation. Flushing. Hypotension. Chest pain. Arrythmias. Bradycardia. Headache. Seizures. Movement disorders. Injection site reactions.

Question 50

Ondansetron:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 50

Actions:
Anti-emetic.

Highly specific and selective Serotonin 5HT3 receptor antagonist. Also a low-affinity dopamine receptor antagonist. Seretonin 5HT3 and dopamine receptors are located centrally in chemoreceptor trigger zone, outside the blood-brain barrier and peripherally at Vagus nerve terminals.

Inhibits serotonin from stimulating afferent nerves that project to the vomiting centre in the medulla oblongata, such as the vagal and splanchnic nerves, and therefore preventing the vomiting reflex.

A – Parenteral. D – Plasma Proteins. M – Liver.
E - Urine.

Question 51

Oxygen:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 51

Dose / Route:
As required.

Indicated:
SpO2 <94% or <88% in COPD.
Major trauma.
Medical emergencies.

Contraindicated:
Explosive environments.

Cautions:
Defibrillation, prolonged use in COPD patients.

Side effects:
Drying and irritation to mucous membranes.

Question 52

Oxygen:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 52

Actions:
Medical Gas.

Increases PaO2 in lungs making more O2 available to diffuse into the circulatory system, providing a greater PaO2 at tissue level supporting aerobic respiration and increasing saturations.

A – inhaled. D – Haemoglobin. M - . E - Exhaled.

Question 53

Paracetamol:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 53

Dose / Route:
1g PO/IV - Adults AND over 50kg.

Indicated:
PO: Mild to moderate pain, Pyrexia with discomfort. IV: Part of a balanced analgesic regimen for severe pain.

Contraindicated:
Paracetamol in last 4 hours (6 hours in patients with renal impairment) or >4 g in last 24 hours.
Allergy.

Side effects:
Extremely rare - Rapid IV administration may cause hypotension.

Question 54

Paracetamol:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 54

Actions:
Analgesic.

Its complete pharmacology is unclear. It is believed to act to non-selectively inhibit COX from synthesising prostaglandins, decreases nociceptor stimulus frequency and strength.

Antipyretic effects from acting on the heat-regulating centres of the hypothalamus to cause peripheral vasodilation, sweating, and therefore heat dissipation.

A – Parenteral/Enteral. D – Plasma Proteins.
M – Liver. E – Urine.

Question 55

Reteplase:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 55

Dose / Route:
10 units reconstituted with 10ml WFI - IV.

Indicated:
STEMI <12 hours from onset where PPCI not readily available.

Contraindicated:
As from checklist.

Side effects:
Bleeding, Arrhythmias, Anaphylaxis, Hypotension.

Question 56

Reteplase:

Actions & A&P.

Answer 56

Actions:
Thrombolytic.

Glycosylated human tissue plasminogen activator (tPA), which cleaves plasminogen to synthesise Plasmin, to break down Fibrin strands of thrombus.

Reteplase binds to fibrin rich clots via the fibronectin finger-like domain and the Kringle 2 domain. The protease domain then cleaves the Arg/Val bond in plasminogen to form plasmin. Plasmin in turn degrades the fibrin matrix of the thrombus, thereby exerting its thrombolytic action.

Question 57

Salbutamol:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 57

Dose / Route:
5 mg NEB (2.5mg/2.5ml or 5mg in 2.5ml).

Indicated:
Acute asthma attack where inhaler therapy has failed to relieve symptoms.
Expiratory wheeze associated with allergy / anaphylaxis / smoke inhalation / other lower airway cause.
Exacerbation of COPD.

Contraindicated:
None.

Cautions:
Hypertension, Angina, Overactive thyroid, Late pregnancy, Beta blocker (can cause severe HTN, use 1/2 doses).
In COPD, limit nebulisation to <6 minutes.

Side effects:
Tremors, Tachycardia, Palpitations, Headache, Feeling of tension, Peripheral vasodilation, Muscle cramps, Rash.

Question 58

Salbutamol:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 58

Actions:
Selective B2 Adrenoreceptor agonist.

Moderately selectively agonises B2 receptors found in the pulmonary system, increasing cAMP production, leading to relaxation of smooth muscle in medium and smaller airways, and subsequent bronchodilation.
Also enhances muco-ciliary clearance and inhibits the release of bronchoconstricting agents from mast cells.
Nebulisation helps to moisten airway, further relieving symptoms. Short onset of effects (3-5 mins).
Once B2 receptors are saturated, salbutamol acts on B1 cardiac receptors causing tachycardia, and alpha receptors causing muscle tremors.

A – Inhaled. D – 10% bound to Plasma Proteins. M – Liver. E – mostly unchanged in Urine.

Question 59

0. 9% Sodium Chloride:
1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 59

Dose / Route:
IV/IO 250ml – 2L.

Indicated:
Medical conditions with / without haemorrhage, Trauma related haemorrhage, Burns, Limb crush injury.
As a flush to confirm patency of an IV or IO cannula. As a flush following drug administration.

Contraindicated:
None.

Side effects:
Over infusion may lead to pulmonary oedema.

Question 60

0.9% Sodium Chloride:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 60

Actions:
Isotonic fluid.

Increases intravascular fluid volume, to raise cardiac output and improve perfusion.

Considerations:
Burns >25% - 1L (max). 
Limb Crush – 2L bolus (max). 
Trauma – 250ml dose (titrate to maintain 60mmHG (penetrating torso) or 90mmHG (penetrating limb / blunt). 
Medical – 250ml (1L bolus in sepsis).

Question 61

Sodium Lactate Compound:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 61

Dose/Route: IV/IO 250ml – 2L.

Indicated:
Blood / Fluid loss where NaCl 0.9% is not available.
Dehydration.

Contraindicated:
DKA coma / pre-coma.
Neonates.

Cautions:
Not to be used in limb crush injury unless NaCl 0.9% is not available.
Renal failure. Liver failure.

Side effects:
Over infusion can precipitate heart failure.

Question 62

Sodium Lactate Compound:

Actions & A&P;

Answer 62

Actions:

Increases intravascular fluid volume to increase cardiac output, mainly consists of Na with some K and Cl.

Question 63

Syntometrine:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 63

Dose/Route:
500 mcg ergometrine with 5 units of oxytocin IM.

Indicated:
PPH <24 hours post delivery of infant where uterine massage has failed.
Miscarriage with a life-threatening bleed and confirmed diagnosis.

Contraindicated: 
Allergy.
Active labour.
Severe cardiac / liver/ kidney disease.
HTN and severe pre-eclampsia.
Possibility of multi pregnancy / Foetus still in utero.

Side effects:
Nausea, Vomiting, Abdominal pain, Headache, HTN, Bradycardia, Chest pain, Anaphylaxis reactions.

Question 64

Syntometrine:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 64

Actions:
Uterine contractor (Ergometrine maleate and Oxytocin).

Binds to 5HT receptors found in the muscle surrounding blood vessels and the uterus, which stimulates the muscles of the uterus to contract and make it very small, and smooth muscle of the blood vessels of the uterus also contract causing vasoconstriction, reducing blood loss.

A – Parenteral. D – 10% bound to Plasma Proteins.
M – Liver & Kidneys. E – Urine.

Question 65

Tenecteplase:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 65

Dose / Route: 6000 – 10,000 units IV.
Presentation: 10,000 units to reconstitute with 10ml WFI, or 8000 units to reconstitute with 8ml WFI.

(Fibrin specific tissue Plasminogen Activator (tPA)

Indicated: 
Acute STEMI (onset <6 hours) where PPCI is not readily available.

Contraindicated:
See checklist.

Side effects:
Bleeding, Arrhythmias, Anaphylaxis, Hypotension.

Question 66

Tenecteplase:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 66

Actions:
Fibrin specific Fibronolytic.

Binds to rich fibrin component of a thrombus via fibronectin finger like domain, selectively converts thrombus bound plasminogen into plasmin, which degrades fibrin mesh of the thrombus.
In the absence of a thrombus, tenecteplase will have little effect on converting circulating plasminogen to plasmin.

A – Parenteral. D – Vascular. M – Liver. E – Renal.

Question 67

Tetracaine 4% gel:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 67

Dose / Route:
1 g or 1.5 g Topical with transparent occlusive dressing.

Indicated:
Venipuncture in non-urgent situations in needle-phobic patients.

Contraindicated: 
Time critical procedures - Venipuncture needed <15 minutes.
Allergy (to cream or dressing).
Pregnant / Breast feeding.
<1 month old.
Open wounds / broken skin.

Cautions:
Allergy to Elastoplast / adhesive dressing.

Side effects: Mild vasodilation of the area, occasional local irritation.

Question 68

Tetracaine 4% gel:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 68

Actions:
Local anaesthetic agent.

Properties that allow the anaesthetic to penetrate intact skin providing numbness to the applied area.

Stabilises the neuronal membrane, and prevents initiation and transmission of nerve impulses, thereby effecting local anaesthesia. Affects sodium channels and inhibits depolarisation.

Question 69

Tranexamic Acid:

1. Dose/Route?
2. Indication?
3. Contra-indications?
4. Cautions?

Answer 69

Dose / Route:
1g in 10ml IV over 10 mins (2x 500mg in 5ml vials).

Indicated:
Time critical injury where internal / external haemorrhage expected.

Step 1 / 2 trauma tool Positive.
Women suffering PPH (used alongside uterotonic drugs).

Contraindicated:
Isolated head injury.
Bleeding ceased.
Critical interventions required.

Side effects:
Rapid administration might rarely cause hypotension.

Question 70

Tranexamic Acid:
Actions & A&P;
A = Absorption, D = Distribution, M = Metabolism,
E = Excretion

Answer 70

Actions:
Anti-fibrinolytic.

Competitive inhibitor of plasminogen by binding to lysine receptor sites in the Kringle domain, preventing plasminogen being converted into plasmin, and so prevents the break down of Fibrin strands keeping the clot intact.

A – Parenteral. D – 3% bound to plasminogen.
M – Liver. E - >95% unchanged in urine.