Pharmacology Flashcards
What electrolye imbalance often precipitates digoxin toxicity
Hypokalaemia
Presentation of quinine toxicity
Tinnitus
Metabolic acidosis
Flash pulmonary oedema
Visual problems
Hypoglycaemia
ECG finding in quinine toxicity
Prolonged QRS
How give opioids initially if patient in acute severe pain
IV morphine in 1-2mg boluses until comfortable
Which antibiotics avoid in G6PD
Quinolones
Nitrofurantoin
Chloramphenicol
Sulphonamides
How long give HRT for in premature menopause
Until 50
Which drugs precipitate lithium toxicity
Diuretics
NSAIDs
How differentiate serontonin syndrome from NMS
NMS= rigidity, hyporeflexia
SS= hyperreflexia, myoclonus
Drugs which induce P450 system
antiepileptics: phenytoin, carbamazepine
barbiturates: phenobarbitone
rifampicin
chronic alcohol intake
griseofulvin
smoking
Drugs which inhibit P450 system
antibiotics: ciprofloxacin, erythromycin
isoniazid
omeprazole
amiodarone
allopurinol
imidazoles: ketoconazole, fluconazole
SSRIs: fluoxetine, sertraline
ritonavir
sodium valproate
acute alcohol intake
When measure phenytoin levels
Just before next dose
When measure ciclosporin levels
Just before dose
When measure digoxin levels
6hrs post dose
Buprenorphine MOA
Kappa-opioid receptor antagonism and mu-opioid receptor agonism
How treat anaphylactoid reactions to IV acetylcysteine
Stop infusion and restart at lower infusion
Give neb salbutamol too as can cause bronchoconstriction
What is an anaphylactoid reaction
Non IgE immune mediated mast cell release
Ciclosporin side effects
Everything raised
- K+
- HTN
- glucose
- fluid retention
- gum hypertrophy
Nephro and hepatotoxic
What is given for HER2 positive breast cancer
Trastuzumab (herceptin)
Problem of trastuzumab
Cardiotoxic
What give if high risk for VTE but severe renal impairement
Unfractionated heparin
Which drugs can cause urinary retention
tricyclic antidepressants e.g. amitriptyline
anticholinergics e.g. antipsychotics, antihistamines
opioids
Presentation of organophosphate poisoning
Accumulation of ach
- Salivation
- Lacrimation
- Urination
- Defecation/diarrhoea
- cardiovascular: hypotension, bradycardia
- small pupils
Management of organophosphate poisoning
Atropine
Which painkiller can interact with SSRI and cause serotonin syndrome
Tramadol
Criteria for liver transplant in paracetamol OD
Arterial pH <7.3 24 hours post
Main side effect of taking mag sulph tablets
Diarrhoea
Who is diclofenac avoided in
Any patient with history of any vascular disease
When stop metformin
MI
AKI
Infection
Diarrhoeal illness
Can increase risk of lactic acidosis
How manage adrenaline induced ischaemia
Phentolamine
Drug causes of urticaria
aspirin
penicillins
NSAIDs
opiates
Organophosphate poisoning presentation
DUMBELS’:
D: defaecation & diaphoresis.
U: urinary incontinence.
M: miosis (pupil constriction).
B: bradycardia
E: emesis.
L: lacrimation.
S: salivation
How differentiate chronic lithium use tremor from overdose
Fine= chronic use
Coarse= overdose
How give acetylcysteine
1 hour infusion
Management of beta blocker OD
If bradycardic give atropine
Management of digoxin toxicity
Digibind- specific neutralising antibodies for digoxin
How does amiodarone cause hypothyroidism
Thought to be due to wolff chaikof effect where levels of thyroxine really high so thyroid stops producing
How does amiodarone cause hyperthyroidism
Type 1- excess iodine induced thyroxine synthesis
Type 2- autoimmune destruction of thyroid
How manage type 1 amiodarone induced thyrotoxicosis
Carbinmazole
How manage type 2 amiodarone induced thyrotoxicosis
Steroids
Lithium toxicity management
mild-moderate toxicity may respond to volume resuscitation with normal saline
haemodialysis may be needed in severe toxicity
sodium bicarbonate is sometimes used but there is limited evidence to support this. By increasing the alkalinity of the urine it promotes lithium excretion
Ecstasy overdose
neurological: agitation, anxiety, confusion, ataxia
cardiovascular: tachycardia, hypertension
hyponatraemia
this may result from either syndrome of inappropriate ADH secretion or excessive water consumption whilst taking MDMA
hyperthermia
rhabdomyolysis
Which antibiotics are ototoxic
Aminogylcosides
Which drugs can precipitate digoxin toxicity
Amiodarone
Verapamil
Diltiazem
Thiazides
Loop diuretics
Effect of taking alcohol with paracetamol OD
Protective as inhibits P450 system
What increases risk of hepatotoxicity in pracetamol OD
P450 inducers
Chronic alcoholism
HIV
Malnourished
What effect does inducing or inhibiting the P450 system have on warfarin
If induce then enhance clearance meaning becomes less effective so INR will drop
When can use activated charcoal in paracetamol OD
If within 1 hour
Digoxin toxicity presenation
Unwell
N&V
Anorexia
Confusion
Yellow green vision
Arrythmias
Gynaecomastia
Which overdose presents with yellow green vision
Digoxin
Aspirin overdose presentation
Hyperventilation
Tinnitus
Glucose abnormalities
Lethargy/confused
N&V
ABG findings in aspirin OD
Early resp alkalosis
Followed by metabolic acidosis
Management of aspirin OD
Charcoal if early
May need sodium bicarb IV and haemodialysis
How manage iron tablet overdose
Desferrioxamine
How manage antifreeze overdose
Fomepizole is antidote
What are the 2 potassium sparing diuretics
Amiloride
Aldosterone antagonists
How does amiloride work
Blocks sodium channels in DCT
Acts as K+ sparing diuretic
What do if develop hypothyroidism on amiodarone
Continue amiodarone
Give thyroid replacement
How are organophosphates so poisonous
Acetylcholinesterase inhibitors which leads to accumulation of acetylcholine
What must avoid when combining diuretics
2 of
- amiloride
- spironolactone
- ACEi
Together
Which antibiotic avoid in seizure patients
Quinolones as reduce seizure threshold
What does POM mean on medication
Prescription only
LSD toxicity
Symptoms
- hallucination
- paranoia
- headache
- palpitations
Obs
- hyperthermia
- hypertension
- tachycardia
- mydriasis
Best option for motion sickness
Transdermal hyoscine
Options for motion sickness
Transdermal hyoscine 1st line
Cyclizine 2nd line
Side effects of nifedipine and amlodipine
Flushing
Ankle swelling
Headache
How are digoxin levels monitored
No monitoring unless toxicity suspected
Drugs which can interact to cause serotonin syndrome
Triptans
St Johns Wort
MDMA
SSRIs
MAOi
Amphetamines
Tramadol
Lithium toxicity precipitants
Dehydration
Renal failure
NSAIDs
Diuretics
Presentation of cocaine OD
Cardio
- arrythmias
- vasospasm
Neuro
- agitation
- seizures
- hypertonia/reflexia
Psychiatric
- psychosis
Ischaemic colitis
What need to consider if someone who has taken cocaine presents with abdo pain or rectal bleeding
Mesenteric ischaemia
Presentation of anti-freeze posioning
Like alcohol intoxication- confusion, slurred speech, dizziness
Metabolic acidosis
Tachycardia and HTN
AKI
Who is antihistamines CI in
HF patients
What do with metformin if diarrhoeal illness
Suspend as increases risk of lactic acidosis
Which CCB most inotropic
Verapamil and so most likely to induce HF
How manage LSD toxicity
For agitation give benzos
May require ITU support
Presentation of hypomagnaesaemia
Similar to hypocalcaemia
If metformin not tolerated due to GI side effects what do
Give modified release version
Which drug causes corneal opacities
Amiodarone
Causes of hypomagnesaemia
PPIs and diuretics
Alcohol use chronically
Hypercalcacemia
Hypokalaemia
Management of paracetamol OD
If staggered (over 1 hour) give right away
Ideally measure levels at 4 hours then give if above certain level
If 8-24 hours after and has consumed over 150mg/kg then give
If present over 24 hours after and jaundiced, hepatic tenderness, paracetamol level raised or ALT raised
Presentation of GHB (gamma hydroxybutyric acid)
Early CNS depression with coma, bradycardia and resp distress
Then quick recovery as short half life
What drug intoxication presents with resp depression, coma and then quickly recovers
Gamma hydroxbutyric acid
Difference between muscarinic and nicotinic receptors
Nicotinic receptors are found in the CNS and NMJ
Muscarinic are found in organs
What is suxamethonium
Nicotinic agonist used as depolarising muscle relaxant
What is atracarium
Nicotinic antagonist used as non-depolarising muscle relaxant
What is a beta 1 agonist
Dobutamine used as inotrope
GABA agonists
Benzos
GABA antagonists
Flumenazil
Serotonin antagonists
Ondensatron
Alpha antagonist
Tamsulosin
Doxazosin for HTN
Alpha 1 agonists
Phenylephrine used for nasal decongestion
Alpha 2 agonists
Biromidine used for glaucoma
Histamine-1 antagonists
Normal anti-histamines like loratadine
Histamine-2 antagonists
Ranitidine used as antacid
Which CCB can you used in HF
Amlodipine as little effect on myocardium- more affects peripheral vascular smooth muscle
What are the 3 places CCBs can act
On voltage gated calcium channels which are present in
- myocardium
- nervous system
- vascular smooth muscle
What are the different types of CCB
Dihydropyridines which act more on vascular smooth muscle
Verapamil which is very inotropic and acts on heart
What are the 2 types of dihydropyridines
Short acting- nifedipine
Longeracting- amlodipine
What is main side effect of short acting dihydropyridines (nifedipine)
Tachycardia as causes peripheral vasodilation
Rank CCBS in terms of inotropic ability
Most= verapamil- avoid in HF
Diltiazem- used with caution in HF
Dihydropyridines- fine in HF
In beta blocker overdose what use
Atropine but if resitant can use glucagon
How manage methanol posioning
Ethanol or fomepizole
How manage cyanide poisoning
Hydroxycobalamin
How manage lead poisoning
Dimercaprol
How manage CO poisoning
100% oxygen
Hyperbaric chamber
How long before can increase metformin dose
1 week
If suspect digoxin toxicity what do
Cease medication
Digoxin concentrations should be measured within 8-12 hours of the last dose to assess for the plasma concentration.
TCA overdose presentation
Anticholinergic effects- mydriasis, dry mouth, blurred vision
If severe- arrythmias, seizures, metabolic acidosis
ECG changes in TCA OD
sinus tachycardia
widening of QRS
prolongation of QT interval
Which HTN drug causes gingival hyperplasia
Amlodipine
What is caustic substance ingestion
Corrosive substance ingesion
Management of corrosive substance ingestion
A-E
IV PPI
Upper GI endoscopy if symptomatic to assess ulceration with zargar classification
Risks of corrosive susbstance ingestion
GI ulceration and perforation
Upper airway injury
Aspiration pneumonia
Infection
Long term risks of corrosive substance ingestion
Strictures, fistulae, gastric outlet obstruction
Upper GI carcinoma (estimated 1000-3000 fold increased risk)
MOA of aspirin
Non-reversible COX 1 and 2 inhibitor which prevents productino of thromboxane A2
Management of heparin induced thrombocytopenia
Direct thrombin inhibitor- argatroban
What do if taking metformin and need CT with contrast
Stop for 48 hours
Contraindications for sildenafil
Taking nitrates or nicorandil
Stroke or MI within 6 months
Hypotension
MOA of UFH vs LMWH
Both activate antithrombin III
UFH forms a complex which inhibits factors- Xa, IXa, Xia and XIIa
LMWH forms a complex which inhibits factor Xa
Adverse side effects of all heparins
Bleeding
Thrombocytopenia
Hyperkalaemia
Osteoporosis
Side effects of amiodarone
Thyroid- hyper and hypo
Corneal deposits
Pulmonary fibrosis
Photosensitivity
Slate grey
Peripheral neuropathy
Long QT
Bradycardia
Best management ofHow give HRT to reduce DVT risk
Transdermal combined
If someone is found next to a bottle of pills and has jaw clenched with uupward deviation of eyes, what is going on
Oculogyric crisis due to metoclopramide or antipschotic intake
Management of oculogyric complications
Procyclidine
Verapamil side effects
Bradycardia
HF
Flushing
Constipation
A 2-year-old boy is recovering following an uncomplicated appendicectomy, first line analgesia
Paracetamol
If patient has post mastectomy arm pain what give
Pregabalin
What must do before giving flecainide
Echo to check for structural heart problems
Management of hypomagnaseamia
Under 0.4 or tetany, arrythmias seizures
- IV mag sulph
Over 0.4
- oral magnesium sulphate salts
Side effect of oral mag sulph salts
Diarrhoea
What monitor with statins
LFTs for 1 year
What monitor with amiodarone
TFT
LFT
What monitor with ACEi
U&Es annually
What monitor with azathioprine
FBC
LFT
Maximum dose of paracetamol/day
4g
If someone is vomiting post op what want to try and do with analgesia
IV analgesia
Carbon monoxide poisoning presentation
Headache- most common
N&V
Flushed skin
Confusion
Investigations for CO poisoning
Pulse oximetry will be normal
Blood gas necessary
ECG to look for iscahemia
What are normal carboxyhaemoglobin levels
In smoker <10%
Non-smoker <3%
What counts as elevated carboxyhaemoglobin levels
Symptomatic 10-30%
Severe toxicity if >30%
Indications for haemodialysis in aspirin OD
Pulmonary oedema
Severe met acidosis
If someone on carbamazepine starts to develop seizures as carbamazepine levels are subtherapeutic, waht is cause
Autoinduction of liver cells which have increased clearance
Management of bleach intake
Asymptomatic
- observe and monitor, IV PPIs
Symptomatic
- IV PPI and endoscopy for early classification with zargar scale
If undergo cardiac surgery what medication is given to patients to prevent clotting
Heparin
Which drug should be administered to normalise a cardiac surgery patients clotting prior to decannulation and chest closure?
Protamine sulphate as they are heavily heparinised during surgery
A 58-year-old male takes ciclosporin after a recent liver transplant. Two weeks later, he develops flu-like symptoms, a fever of 39ºC, and a reduced urine output. What drugs may cause this presentation?
Man is rejecting the liver as ciclosporin levels have been reduced due to induction of P450 system
Which NSAID should be avoided in CVD
Diclofenac
Management of theophylline toxicity
Haemodialysis
What happens if take allopurinol and azathioprine together
Azathioprine toxicity leading to myelosuppression
What does a black triangle on a medication mean
That it is a new medicine
What must do if any side effects are experiences on a medication with black triangle
Report immediately
What is the yellow card scheme
The Yellow Card scheme has become the standard way to report adverse reactions to medications. It is run by the Medicines and Healthcare products Regulatory Agency
When should always report something via yellow card scheme
All adverse drug reactions on medicines with black triangle
Any adverse reaction in a child
All lifethreating, fatal or disabling adverse reactions in an established drug or vaccine
Digoxin MOA
Inhibits the Na+/K+ ATPase pump
What must be done before starting TB medications
LFTs for isoniazid
U&Es and visual acuity for ethambutol
What is eGFR cutoff for metformin use
30
Is HRT contraindicated if migraine history
No
What drug causes bluish tinge to vision
Viagra (bluey)
Drug induced thrombocytopenia
NSAIDs
diuretics: furosemide
anticonvulsants: carbamazepine, valproate
heparin
Can you still get digoxin toxicity if in therapeutic range
Yes
Complications of illicit opioid misuse
VTE
Hepatitis infection
Bacterial infections secondary to injectiing
Overdose
Social problems- prostitution etc
Drug causes of pulmonary fibrosis
amiodarone
cytotoxic agents: busulphan, bleomycin
anti-rheumatoid drugs: methotrexate, sulfasalazine
nitrofurantoin
ergot-derived dopamine receptor agonists (bromocriptine, cabergoline, pergolide)
If a drug is 2%, what does that mean
That 2g of the drug are dissolved in 100ml
