Pharmacology Flashcards
1
Q
Define Affinity
A
the tendency of a molecule to bind to a receptor
2
Q
Define Efficacy
A
how well an agonist achieves a response
3
Q
Define an antagonist
A
A chemical that opposes the action of another chemical.
Therefore, antagonists should have no action on their targets in the absence of an agonist.
4
Q
Drugs that can cause hyperkalaemia (10)
A
THANKS CYCLE PENines
T: Trimethoprim
H: Heparin (LMWH - inhibition of aldosterone synthesis)
A: ARBs and ACE-Is (reduce aldosterone -> potassium retention)
N: NSAIDs
K: K+ sparing diuretics
S: Succinyl choline
CYCLE: Cylosporins and Tacrolimus
PENines: Pentamidine
5
Q
Drugs that can cause hypokalaemia (7)
A
DIG CBT D: Diuretics and laxatives I: Insulin G: Gentamicin C: Corticosteroids (Pred) B: Beta-2-agonists T: Theophylline
6
Q
Drugs that can cause hypercalcaemia (2)
A
- Vit D
- Thiazide diuretics
7
Q
Drugs that can cause hypocalcaemia (3)
A
- Bisphosphonates
- Corticosteroids
- Loop diuretics
8
Q
Drugs that can cause hypernatraemia (1)
A
- Lithium
9
Q
Drugs that can cause hyponatraemia (5)`
A
- Antidepressants (SSRIs, tricyclics)
- Laxatives
- Loop diuretics
- Thiazide diuretics
- Potassium-sparing diuretics
- Sulfonylureas
- Carbamazepine
- Vincristine
- Cyclophosphamide
10
Q
Drugs that should be stopped before surgery? (8)
A
- Aspirin (unless recent ACS, coronary artery stent or ischaemic stroke) -> replace with LMWH or unfractionated heparin
- COCP
- MAOIs
- Lithium (24 hrs before major surgery only, monitor fluids and electrolytes in minor surgery)
- Potassium-sparing diuretics on morning of surgery
- ACE-Is and ARBs 24 hrs before
- Herbal medicines
- Let surgeon know if on tricyclic antidepressants
11
Q
Drugs to be stopped in AKI
A
Direct nephrotoxics:
- ACE-Is (small creatinine rise expected when initiating, recheck in 1 week)
- ARBs
- Diuretics (Furosemide, Potassium-sparing)
- NSAIDs
- Contrast media
Stop in AKI:
- Allopurinol (can accumulate) - max of 100 mg OD until improves
- Hypoglycaemic agents - modified-release
- Gentamicin/Vancomycin
- Lithium
- Methotrexate
- Metformin (avoid if GFR <30)
- CCBs
- Tetracyclines
- Trimethoprim
- Statin (if rhabdomyolysis)
12
Q
Drugs that can cause confusion
A
Sedatives:
- Benzos
- Opioids
- Glucocorticoids (Prednisolone)
13
Q
Drugs that can cause hyperglycemia
A
- Glucocorticoids (Pred)
- Atypical antipsychotics (Clozapine)
- Thiazide diuretics
- Statins
14
Q
Trimethoprim:
- Dose, CI, Cautions, SEs
- Interaction
- Pregnancy
A
- Dose: 200 mg BD for 3 days (7 days in males
- CI: Blood dyscrasias
- Cautions:
- Blocks folate metabolism, may exacerbate pre-existing folate deficiency, generally doesn’t prevent short term use (do NOT prescribe with methotrexate)
- Porphyrias
- Renal dysfunction: half dose if eGFR < 15
- SEs: Diarrhoea, vomiting, electrolyte imbalance, headache, nausea, skin reactions
- Interactions: METHOTREXATE
- Teratogenic in FIRST TRIMESTER
15
Q
Nitrofurantoin:
- Dose, CI, Cautions
- Pregnancy
A
- Dose: 50 mg QDS for 3 days (7 days in males)
- Avoided if eGFR less than 45
- Used with caution if eGFR 30-44 (short course only: 3-7 days)
- CI: Porphyrias, G6PD deficiency, eGFR < 45
- Cautions:
- Anaemia, DM, electrolyte imbalance, folate deficiency, urine may be yellow/brown
- Teratogenic at TERM
16
Q
Anticoagulation before surgery
A
- If AF-related stroke/TIA then need formal anticoagulation with treatment dose LMWH
- Without this Hx, no need for formal anticoag
- BNF recommends that if INR > 1.5 before elective surgery, phytomenadione (Vit K) 1-5 mg PO using IV prep is indicated
17
Q
Sumatriptan
- Doses (PO, SC, Intranasal)
- CIs, Cautions
- SEs
- Pregnancy
A
-
Dose:
- PO 50-100 mg for 1 dose, followed by 50-100 mg after at least 2 hrs if required
- SC 3-6 mg for 1 dose, followed by 3-6 mg after at least 1 hr if required
- Intranasal 10-20 mg in one nostril, again after at least 2 hrs if required
- CIs: IHD, mild uncontrolled HTN, mod-sev HTN, peripheral vascular disease, previous cerebrovascular accident, previous MI, previous TIA, Prinzmetal’s angina
- Cautions: Predisposing coronary artery disease factors, elderly, Hx of seizures, mild controlled HTN, risk factors for seizures
- SEs: Dizziness, drowsiness, dyspnoea, flushing, myalgia, nausea, vomiting, pain, skin reactions, temp sensation altered
- Pregnancy: best to avoid if possible due to limited evidence
- Consider dose reduction to 25–50 mg in mild to moderate hepatic impairment
18
Q
Propranolol
- Dose
- CIs and cautions
- SEs
A
- Dose: 80 - 240 mg daily in divided doses
- CIs: Asthma, COPD, hypotension, bradycardia, metabolic acidosis, 2nd or 3rd degree AV block, severe peripheral arterial disease, sick sinus syndrome, uncontrolled HF, pheochromocytoma, Prinzmetals angina
- Cautions: DM, myasthenia gravis, portal hypertension, psoriasis, may mask hypoglycaemia or thyrotoxicosis
- Elderly STOPP criteria:
- In combo with verapamil or diltiazem
- With bradycardia (HR<50bpm)
- DM with frequent hypoglycaemia episodes
- History of asthma requiring
- Elderly STOPP criteria:
- SEs: abdo discomfort, confusion, depression, diarrhoea, dizziness, dry eye, dyspnoea, erectile dysfunction, fatigue, headache, HF, nausea, paraesthesia, PVD, rash, sleep disorder, syncope, visual impairment, vomiting
19
Q
Topiramate
A
- Dose: 50 - 100 mg daily, two divided doses, taken at night. Start with 25 mg OD for 1 week, increased in steps of 25 mg each week, max 200 mg daily
- ENZYME INDUCER
- Risk of suicidal thoughts and behaviour
- Cautions: acute porphyria’s, risk of metabolic acidosis
- Pregnancy: Use of highly effective contraception and fully informed of risks or avoid altogether
- Breastfeeding: AVOID
- Renal impairment: half dose if creatinine clearance < 70
20
Q
Drug-induced liver injury (8 drug causes)
A
-
Flucloxacillin and Co-Amoxiclav
- Cholestatic hepatitis and jaundice
- Idiosyncratic, not dose-related
- Onset may be delayed for up to 2 months following Tx
-
Paracetamol
- Causes a dose-dependent acute liver injury → can lead to acute liver failure
-
NSAIDs
- Idiosyncratic hepatitis, resolves in most cases after the termination of drug therapy
- Classically causes a cholestatic hepatitis
- Aspirin can also cause hepatitis but tends to be dose-related
-
Anti-TB drugs (RIPE)
- Can cause liver injury
-
Methotrexate
- Severe fibrosis and cirrhosis if not adequately monitored
-
Amiodarone
- Steato hepatitis
- Statins: can cause a mild transaminitis (raise in AST/ALT), monitor LFTs in those with mild liver disease
21
Q
Typical dose of:
Paracetamol
A
0.5 - 1 kg QDS
22
Q
Typical dose of:
Ibuprofen
A
200- 400 mg TDS
23
Q
Typical dose of:
Codeine
A
30 - 60 mg QDS
24
Q
Typical dose of:
Co-codamol
A
2 tabs QDS
25
Typical dose of:
| Cyclizine
50 mg TDS
26
Typical dose of:
| Metoclopramide
10 mg TDS
27
Typical dose of:
| Amoxicillin
500 mg TDS
28
Typical dose of:
| Clarithromycin
500 mg BD
29
Typical dose of:
| Lansoprazole
15-30 mg OD
30
Typical dose of:
| Omeprazole
20-40 mg OD
31
Typical dose of:
| Aspirin
75-300 mg OD
32
Typical dose of:
| Clopidogrel
75-300 mg OD
33
Typical dose of:
| Atenolol
25-100 mg OD
34
Typical dose of:
| Ramipril
1.25-10 mg OD
35
Typical dose of:
| Furosemide
20 mg OD to 80 mg BD
36
Typical dose of:
| Amlodipine
5-10 mg OD
37
Typical dose of:
| Levothyroxine
25-200 micrograms OD
38
Typical dose of:
| Metformin
500 mg OD to 1 g BD
39
Typical dose of:
| Atorvastatin
10-80 mg OD (at night)
40
Typical dose of:
| Simvastatin
10-40 mg OD (at night)
41
Drugs that lower seizure threshold (8)
- Alcohol/cocaine/amphetamines
- Quinolones: ciprofloxacin, levofloxacin
- Aminophylline and theophylline
- Bupropion
- Methylphenidate (ADHD med)
- Mefenamic acid
- P450 Inducers / inhibitors
- Withdrawal of benzos, baclofen, hydroyzine
42
Drugs not administered daily? (7)
- Bisphosphonates: Weekly (Can be daily or monthly too)
- Hydroxocobalamin: 2-3 monthly
- Injectable antipsychotics: Weekly-monthly
- Methotrexate: Once a week
- Injectable RA drugs: Every 2 weeks
- Goserelin: 3 monthly
- Implants: 3 monthly
43
Presentation of rhabdomyolysis
- Muscle swelling and tenderness
- Weakness
- Grey/brown urine
- Raised CK
May lead to:
- Renal failure
- Hyperkalaemia
44
What can increase risk of rhabdomyolysis?
STATINS plus:
- older age
- female
- genetics
- renail impairment
- concomitant diltiazem (max statin dose = 20 mg)
45
Tx of rhabdomyolysis
- IV fluids
- Consider sodium bicarb
- Monitor K+
46
Known teratogenics (10)
- ACE-Is and ARBs
- Antiepileptics, e.g. valproate, carbamazepine, phenytoin
- Cytotoxic agents
- Sex hormones
- Statins
- Lithium salts
- Thalidomide
- Warfarin
- Retinoids
- Abx - tetracyclines, trimethoprim, quinolones, aminoglycosides, sulphonamides
- Sulfonylureas
47
Gentamicin monitoring
Multiple daily dose:
- Peak (1hr post dose): 3-5 mg/litre
- Trough (pre next dose): < 1 mg/litre
If peak is high: decrease dose
If trough is high: increase intervals
Once daily dose:
- 6-14 hrs after start of infusion
- Targets concentration < 1 mg/litre
48
Warfarin strengths and tablet colours
500 micrograms - White
1 mg - Brown
3 mg - Blue
5 mg - Pink
49
Typical dose of:
| Warfarin
1 mg - 15 mg (average = 5 mg)
| OD, same time each day, usually evening
50
Drugs that should be avoided in HF?
- Thiazolididiones (e.g. pioglitazone)
- Verapamil/Dialtezam
- NSAIDs/glucocorticoids (fluid retention)
- Class I antiarrhythmics (flecainide, lidocaine, quinidine)
51
Cytochrome P450
| Substrates (8)
- Warfarin
- COCP
- Statins
- Nifedipine
- Theophylline
- Tricyclics
- Corticosteroids
- Pethidine
52
Cytochrome P450
| Inducers (10)
GPRS Cell Phone (Inducer = electric = phone)
- Griseofulin
- Phenytoin
- Rifampicin
- Sulfonylureas
- Carbamazepine
- Phenobarbitone
- Topiramate
- Smoking
- St John's Wort
- Alcohol - CHRONIC
53
Cytochrome P450
| Inhibitors (12)
SICKFACES.COM (Inhibitor = inhibit getting better = sick)
- Sodium Valproate
- Isoniazid
- Cimetidine
- Ketoconazole
- Fluconazole/Miconazole
- Acute alcohol, grapefruit juice
- Chloramphenicol
- Erythromycin
- Sulfonamides
- Ciprofloxacin
- Omeprazole
- Methotrexate
54
Monitoring Requirements
| Levothyroxine
- Annual TFTs if on maintenance
- After dose adjustment -> wait 6/8 weeks then check TFTs
- Acute illness may affect results
55
Monitoring Requirements
| Amiodarone
- TFTs before Tx and every 6 months after
| - Associated with both hypo- and hyper- thyroidism
56
Monitoring Requirements
| Digoxin
- Heart rate monitored before administration
57
Monitoring Requirements
| Gentamicin
- Narrow therapeutic window -> plasma concentration
58
Monitoring Requirements
| Methotrexate
Before, every 1-2 weeks unstable, 2-3 months after:
- FBC (neutropenia), including ESR
- LFTs
- Renal function
Baseline CXR and then if pulmonary toxicity occurs
59
Monitoring Requirements
| Adalimumab
- Evaluate for active/inactive TB
| - If prev treated for TB, monitor every 3 months for recurrence
60
Monitoring Requirements
| Carbamazepine
- FBC (neutropenia) - look out for SORE THROAT
61
Monitoring Requirements
| Clozapine
- FBCs - leucocytes and differential blood counts
- WCC monitoring weekly for 18 weeks, then fortnightly for 1 year, then monthly
- Close medical supervision during initiation (risk of hypotension and convulsions)
- Lipids and weight at baseline, frequent intervals during first 3 months, 3 monthly for one year, then yearly
- Fasting blood glucose at baseline, 4-6 months then annually
62
Monitoring Requirements
| Lithium
Serum-lithium concentration (0.4 - 1 mmol/litre)
- Higher end in acute treatment
- Measure 12 hr post dose after at least 4 days
- Measure weekly until stabilised
- Measure every 3 months thereafter
- Cardiac function regularly
- TFTs, renal function, calcium and BMI every 6 months
63
Lithium
| Adverse effects
- Fine hand tremor
- Nausea
- Weight gain
- Metallic taste
- Mild polydipsia
- Polyuria
- Alteration of renal function
- Diabetes insipidus
- Hyperparathyroidism
- Hyperthyroidism
64
Lithium
| Toxicity
- Severe hand tremor
- Vomiting and diarrhea
- Blurred vision
- Muscle weakness
- Ataxia
- Dysarthria
- Confusion
- Nystagmus
- Renal failure
- Seizures
- Coma
65
Lithium
| Interactions
ACE-I - increases conc
Diuretics - hypokalaemia and increases concs
NSAIDs - increases concs
Sodium-containing compounds - decreases concs
66
Acetylcysteine indications in paracetamol overdose
- There is a staggered overdose* or there is doubt over the time of paracetamol ingestion, regardless of the plasma paracetamol concentration; or
- The plasma paracetamol concentration is on or above a single treatment line joining points of 100 mg/L at 4 hours and 15 mg/L at 15 hours, regardless of risk factors of hepatotoxicity
- > 150 mg/kg
67
Tx of anaphylaxis
- ABCDE
- Adrenaline
- IV fluids
- Oxygen: 15l/min reservoir mask
- Antihistamines - Chlorphenamine
68
Symptoms of hypoglycemia
- Sweating
- Anxiety
- Blurred vision
- Confusion
- Aggression
69
What drugs can mask hypoglycemia?
Beta-blockers, e.g. propranolol, atenolol
70
Tx of hypoglycemia
- Conscious patients - 10 - 20 g of short-acting carbohydrate (e.g. glass of Lucozade, non-diet drink, three or more glucose tablets, glucose gel)
71
What is lipodystrophy
Present as atrophy/lumps of SC fat at the insulin injection site.
- Can be prevented by rotating injection site
- May cause erratic insulin absorption
72
Digoxin
Toxicity
Features
- Diarrhoea
- N+V
- Confusion
- Anorexia
- Palpitations
- Hallucinations
- General malaise
- Blurred vision
- Weakness
- Arrhythmias
- Syncope
73
Digoxin
Toxicity
Susceptibility factors
- More likely in **older adults** and in **hypokalaemia**
- Renal failure
- Myocardial ischaemia
- Hypomagnesaemia
- Hypercalcaemia
- Hyponatraemia
- Alkalosis
- Hypoxia
- Hypoalbuminaemia
- Hypothermia
- Hypothyroidism
74
Digoxin
Toxicity
Management
- Stop digoxin
- Measure urea and electrolytes (potassium and creatinine) and correct
- Monitor heart rhythm and BP
- Digibind antidote
75
Digoxin
Toxicity
Drugs that increase susceptibility
- Amiodarone - half digoxin dose
- Ciclosporin
- Erythromycin
- Verapamil - reduction of digoxin of 30-50%
- Spironolactone
- Quinine
- Diltiazem
76
Best opioids in renal impairment?
- Mild-mod: oxycodone can be used in place of morphine
| - Severe: alfentanil, buprenorphine and fentanyl
77
Treatment of bone pain in palliative care?
- Strong opioids
- Bisphosphonates
- Radiotherapy
- Denosumab
78
First-line opioid treatment in palliative care
Offer patients with advanced and progressive disease regular oral modified-release (MR) or oral immediate-release morphine (depending on patient preference), with oral immediate-release morphine for breakthrough pain
If no comorbidities use 20-30mg of MR a day with 5mg morphine for breakthrough pain.
For example, 15mg modified-release morphine tablets twice a day with 5mg of oral morphine solution as required
79
How do you increase opioids in palliative care?
Next dose should be 30-50% more
80
General factors that may potentiate warfarin
- Liver disease (impaired synthesis of Vit K)
- P450 inhibitors
- Cranberry Juice
- Drugs that displace warfarin from albumin, e.g. NSAIDs
- Inhibit platelet function, e.g. NSAIDs
81
Prescribing in asthma
| NSAIDs
- 10-20% with asthma will experience worsening of symptoms/bronchospasm after NSAIDs
- NSAID-induced asthma is uncommon in children
- Risk is increased in those with nasal polyps or middle-aged
82
Prescribing in asthma
| Beta-blockers
- May cause bronchospams
| - Best avoided
83
Prescribing in asthma
| Adenosine
- Contraindicated in asthma and COPD
| - Verapamil can be used as an alternative
84
Tx of C.Diff
```
First-line = Metronidazole (mild-mod disease)
Second-line = Vancomycin (severe disease)
```
85
SIADH causes
Characterized by hyponatraemia secondary to dilutional effects of excessive water retention
- Sulfonylureas
- SSRIs, tricyclics
- Carbamazepine
- Vincristine
- Cyclophosphamide
86
When should you add a second diabetes drug?
| And which drugs?
HbA1c > 58 mmol/mol (7.5%)
sulfonylurea
gliptin
pioglitazone
SGLT-2 inhibitor
87
HbA1c targets
```
Lifestyle:
- 48 mmol/mol
Lifestyle and metformin:
- 48 mmol/mol
Any drug which may cause hypolglycemia (e.g. lifestyle and sulfonylurea):
- 53 mmol/mol
```
88
When should you add a third diabetes drug?
| And which drug?
If HbA1c rises to or remains about 58 despite two meds:
- metformin + gliptin + sulfonylurea
- metformin + pioglitazone + sulfonylurea
- metformin + sulfonylurea + SGLT-2 inhibitor
- metformin + pioglitazone + SGLT-2 inhibitor
- OR insulin therapy should be considered
89
If there are no signs of hypoxia, when is oxygen therapy not routinely used?
- MI and ACS
- Stroke
- Obstetric emergency
- Anxiety-related hyperventilation
90
Oxygen management of COPD patient
Before the availability of blood gas use:
| - 28% venturi mask at 4l/min and aim for 88-92%
91
Prescribing in ischaemic heart disease
Use with caution:
- NSAIDs
- Oestrogens (COCP, HRT)
- Varenicline
92
Breastfeeding
| Drugs to avoid (8)
- antibiotics: ciprofloxacin, tetracycline (lymecycline/doxycycline) chloramphenicol, sulphonamides (sulfasalazine)
- psychiatric drugs: lithium, benzodiazepines
- aspirin
- carbimazole
- methotrexate
- sulfonylureas (glipizide, glimepiride)
- cytotoxic drugs
- amiodarone
93
```
Breastfeeding
Safe drugs (7 groups)
```
- antibiotics: penicillins, cephalosporins, trimethoprim
- endocrine: glucocorticoids (avoid high doses), levothyroxine*
- epilepsy: sodium valproate, carbamazepine
- asthma: salbutamol, theophyllines
- psychiatric drugs: tricyclic antidepressants, antipsychotics**
- hypertension: beta-blockers, hydralazine
- anticoagulants: warfarin, heparin
digoxin
94
What defines severe C.diff?
- WCC >15 109/L;
- acutely rising blood creatinine (e.g. >50% increase above baseline);
- temperature >38.5°C; or
- evidence of severe colitis (abdominal signs, radiology).
95
Glucocorticoid SEs
Endocrine
- impaired glucose regulation
- increased appetite/weight gain
- hirsutism
- hyperlipidaemia
Cushing's syndrome
- moon face
- buffalo hump
- striae
Musculoskeletal
- osteoporosis
- proximal myopathy
- avascular necrosis of the femoral head
Immunosuppression
- increased susceptibility to severe infection
- reactivation of tuberculosis
Psychiatric
- insomnia
- mania
- depression
- psychosis
Gastrointestinal
- peptic ulceration
- acute pancreatitis
- ophthalmic
- glaucoma
- cataracts
suppression of growth in children
intracranial hypertension
neutrophilia
96
When do you need to taper withdrawal of systemic corticosteroids?
- received more than 40mg prednisolone daily for more than one week
- received more than 3 weeks of treatment
- recently received repeated courses
97
BNFc
Symbols
POM
Prescription only medicine
98
BNFc
Symbols
CD2, CD3, CD4-1, CD4-2
x1 example
Controlled drugs according to Misuse of Drugs Act and Misuse of Drugs Regulations 2001 (updated 2014)
e.g. Midazolam = CD3
99
BNFc
Symbols
Box - half white, half black
Less suitable for prescribing or is not prescribable
| e.g. Dentinox, Colic Drops
100
BNFc
Symbols
NHS crossed out
Not prescribable under the NHS
e.g. flurazepam capsules
101
BNFc
eGFR calculations
a) Neonate
b) Child > 1yr
a) 30 x height (cm) / serum creatinine (micromol/litre)
| b) 40 x height (cm) / serum creatinine (micromol/litre)
102
Type I allergic reaction
| Symptoms and onset
- Usually occur within minutes to 2 hours of exposure, not always with the first dose
- Symptoms can occur very rapidly with parenteral drug admin (median time to cardiac arrest in fatal anaphylaxis is 5 mins
- Itching, urticaria, hypotension, angioedema, wheeze
103
NB re urticaria
- Can arise due to infection alone so important to determine if the onset was prior to initiation of antibiotic? And did it occur for longer than a few hours after meds stopped?
104
ACE-I and angioedema
Can cause pure angioedema, which can arise many years after the drug has been taken uneventfully
105
Non-allergic drug reactions x5
- Morbilliform rash
- Erythema multiforme (target lesions)
- Fixed drug eruptions (erythematous plaques recur in same place each time causative drug is taken - paracetamol, tetracyclines, NSAIDs)
- Photosensitivity
- Vaccination in presence of high pre-existing antibody levels can result in itchy induration 6-8 hrs later (NO allergic, not harmful)
106
Difference between morbilliform and urticaria
- Morbilliform rash lesions enlarge and become confluent over several days
- Urticaria lesions subside and reappear in different areas
107
Cross Reacting Drugs
| Penicillin (2)
```
- Penicillins and cephalosporins
1st and 2nd gens (pha/fa) - avoid: cefalexin, cefadroxil, cefazolin, cefuroxime, cefoxitin
3rd gens (one/ten/ime) - use with caution: cefuroxime, cefotaxime, ceftazidime, ceftriaxone, cefixime
```
- Penicillins and carbapenems (doripenem, ertapenem, imipenem, meropenem)
- Can safely prescribe aztreonam
108
Common causes of allergic drug reactions (8) (
- Chlorhexidine
- Opioid analgesics
- Non beta-lactam antimicrobials
- Penicillins and beta-lactams
- NSAIDs
- Plasma expanders (hespan, dextran)
- Muscle relaxants
- Radiocontrast media
109
Agents that cause allergic reactions during anesthesia (6)
- Antimicrobials - notably co-amox and teicoplanin
- Chlorhexidine
- Colloids
- Neuromuscular blocking agents (NMBAs), e.g. rocuronium
- Patent blue injection (die for delineating lymph nodes)
- Misc medicines (ondansetron, propofol)
110
Tx of mild and mod allergic reactions
- No systemic reaction
- Fast-acting oral antihistamine (Chlorphenamine)
- Have IM epinephrine available
111
Define severe allergic reaction
- Hypotension
- Laryngeal oedema
- Wheeze
- SpO2 < 92%
- Impaired consciousness
112
First-line Tx for anaphylaxis
a) Adult/Child > 12 yrs
b) Child 6-12 yrs
c) Child < 6 yrs
a) 500 micrograms (0.5mL) IM adrenaline (300 if administered by self)
b) 300 micrograms (0.3mL) IM adrenaline
c) 150 micrograms (0.15mL) IM adrenaline
113
Anaphylaxis antihistamine doses
a) Adult/Child > 12 yrs
b) Child 6-12 yrs
c) Child 6 months - 6 yrs
d) Child < 6 months
a) 10 mg
b) 5 mg
c) 2.5 mg
d) 250 micrograms/kg
Given slow IV or IM
114
Anaphylaxis hydrocortisone doses
a) Adult/Child > 12 yrs
b) Child 6-12 yrs
c) Child 6 months - 6 yrs
d) Child < 6 months
a) 200 mg
b) 100 mg
c) 50 mg
d) 25 mg
Given slow IV or IM
Take at least 2 hrs to work but may help reduce risk of persistent/biphasic reaction
115
How long should you monitor someone after anaphylaxis?
| Follow-up meds?
6-12 hrs
Pred for up to 3 days
Non-sedating antihistamine for up to 3 days
Recommend an alert band
116
Other anaphylaxis Tx (4)
- Neb or IV salbutamol
- Ipratropium
- Aminophylline
- Magnesium
117
MHRA advice re adrenalin auto-injectors
1) Carry two at all times
2) Ambulance phoned after every use even if symptoms improving
3) After administration - lie down with legs raised to maintain blood blow
4) Patient should not be left alone
118
Mast tryptase measurements (3)
- As soon as possible after emergency Tx has started
- 1-2 hrs after onset of symptoms (no later than 4hrs)
- At 24 hrs if possible
119
Warfarin
| Factors that increase sensitivity
- Age > 70 yrs
- Drug interactions, e.g. amiodarone
- Hepatic impairment (baseline INR > 1.4)
- Severe cardiac failure
- TPN
- Low albumin levels
- Low BMI
120
DOACs
| Examples of thrombin inhibitors
- Dabigatran
121
DOACs
| Examples of Factor Xa inhibitors
- Apixaban
- Edoxaban
- Rivaroxaban
122
Tamoxifen
| Duration
Normal used for 5 yrs following tumour removal
123
Tamoxifen
| Adverse effects
- Menstrual disturbance: vaginal bleeding, amenorrhoea
- Hot flushes - 3% of patients stop taking tamoxifen due to climacteric side-effects
- Venous thromboembolism
- Endometrial cancer
124
Analgesic ladder
| Step 1
Non-opioid analgesics
- NSAIDs, aspirin
- Paracetamol
125
Analgesic ladder
| Step 2
Mild opioid analgesics
- Codeine
- Co-codamol (30/500)
- Dihydrocodeine
- Tramadol
126
Analgesic ladder
| Step 3
Strong opioid analgesics
- Morphine
- Methadone
- Fentanyl
- Oxycodone
127
Paroxysmal supraventricular tachycardia
| Acute Tx
Vagal manoeuvres:
- Valsalva manoeuvre: e.g. trying to blow into an empty plastic syringe
- Carotid sinus massage
Intravenous adenosine
- Rapid IV bolus of 6mg → if unsuccessful give 12 mg → if unsuccessful give further 18 mg
- Contraindicated in asthmatics - verapamil is a preferable option
Electrical cardioversion
128
Paroxysmal supraventricular tachycardia
| Prevention
- Beta-blockers
| - Radio-frequency ablation
129
CCBs
Verapamil
Indications
- Angina
- HTN
- Arrhythmias
130
CCBs
Verapamil
Cautions
Should NOT be given with beta-blockers (heart block) or in HF
Due to being a highly negative inotrope
131
CCBs
Verapamil
SEs
- Constipation
- Hypotension
- Bradycardia
- Flushing
132
CCBs
Diltiazem
Indications
- Angina
| - HTN
133
CCBs
Diltiazem
Cautions
Less negatively inotropic than verapamil but caution still needed if HF/beta-blockers
134
CCBs
Diltiazem
SEs
- Hypotension
- Bradycardia
- HF
- Ankle swelling
135
CCBs
Dihydropyridines
Examples
- Amlodipine
- Nifedipine
- Felodipine
136
CCBs
Dihydropyridines
Indications
- HTN
- Angina
- Raynaud's
137
CCBs
Dihydropyridines
Catuions
Affects peripheral vascular smooth muscle more than myocardium so does not result in worsening HF but may therefore cause ankle swelling
138
CCBs
Dihydropyridines
SEs
- Flushing
- Headache
- Ankle swelling
139
Drugs that exacerbate psoriasis
- Beta-blockers
- Lithium
- Antimalarials (chloroquine and hydroxychloroquine)
- NSAIDs
- ACE inhibitors
- Infliximab
- Withdrawal of systemic steroid
- Alcohol
140
Drugs that can precipitate digoxin toxicity
- Amiodarone
- Diltiazem
- Thiazides
- Loop diuretics
- Verapamil
- Ciclosporin
- Quinidine
141
Which drug should be prescribed by trade/brand drug name?
- Tacrolimus
142
Drugs to increase during surgery?
- Patients on long-term corticosteroids should have IV steroids at induction of anesthesia
143
Drugs to stop before surgery?
I LACK OP
- Insulin
- Lithium (24 hrs before major surgery only, monitor fluids and electrolytes in minor surgery)
- Anticoagulants/antiplatelets
- COCP/HRT (4 weeks before)
- K-sparing diuretics (on morning)
- Oral hypoglycaemics (metformin could cause lactic acidosis, others could cause hypoglycemia)
- Perindopril (and other ACE-Is/ARBs) - 24hrs before
NBs:
- Aspirin (unless recent ACS, coronary artery stent or ischaemic stroke) -> replace with LMWH or unfractionated heparin
- MAOIs
- Herbal medicines
- Let surgeon know if on tricyclic antidepressants
144
Four drugs to know CIs for
- Drugs that increase bleeding and a bleeding patient
- Steroids
- NSAIDs
- Antihypertensives
145
Anticoagulants/antiplatelets
| CIs
- Do not give if patient bleeding, suspected bleeding or at risk of bleeding (e.g. long prothrombin time due to liver disease)
- Prophylactic heparin is CI in acute ischaemic stroke due to risk of bleeding into the stroke
- Enzyme inhibitors (e.g. erythromycin) can increase warfarin effects
146
Steroids
| CIs
STEROIDS
- Stomach Ulcers
- Thin skin
- Edema
- Right and left heart failure
- Osteoporosis
- Infection (including candida)
- Diabetes (commonly causes hyperglycemia and uncommonly progresses to diabetes
- cushing's Syndrome
147
NSAIDs
| CIs
NSAID
- No urine (renal failure)
- Systolic dysfunction (heart failure)
- Asthma
- Indigestion
- Dyscrasia (clotting abnormality)
148
Antihypertensives
| CIs
- Bradycardia with beta-blockers and some CCBs
| - Electrolyte disturbances with ACE-Is and diuretics
149
Antihypertensives
| Specific SEs
= ACE-I: dry cough
- B-Blockers: wheeze in asthmatics, worsening acute HF
- CCBs: flushing and oedema
- Diuretics: renal failure
- Loop diuretics: gout
- Potassium-sparing diuretics: hyperkalaemia and gynaecomastia
150
Usual hospital blood clot prophylaxis and exceptions to rule
- LMWH (Dalteparin 5000 units SC OD)
- Exception: bleeding/at risk of bleeding/recent ischaemic stroke
- Compression stockings
- Exception: not in PAD - usually indicated by absent foot pulses, may cause limb ischaemia
151
Usual antiemetic? Dose?
- Cyclizine 50 mg 8-hourly IM/IV/oral
152
When would you not use cyclizine? What's the alternative and dose?
- In cardiac cases as can worsen fluid retention
| - Use Metoclopramide 10 mg 8-hourly IM/IV if heart failure
153
When would you avoid Metoclopramide?
- Parkinson's disease
| - Young women (risk of dyskinesia)
154
Analgesic choice
No pain, PRN
Paracetamol 1 g up to 6 hrly PO
155
Analgesic choice
Mild pain, PRN
Codeine 30 mg up to 6 hrly PO
Or Tramadol
156
Analgesic choice
Severe pain, PRN
Morphine sulphate 10 mg up to 6 hrly PO (oramorph)
| Strength usually 10mg/5mL
Then SC, then IV
157
Analgesic choice
Mild pain, regularly
Paracetamol 1 g 6 hrly PO
158
Analgesic choice
Severe pain, regularly
Co-codamol 30/500
| 2 tablets, 6 hrly, PO
159
What should you be careful of with co-codamol?
It contains paracetamol (500 mg) so check patients other analgesics. Should not be having > 4 g in 24 hrs
160
Primary questions in prescription review?
- Are they risk of bleeding?
- Are they taking too much paracetamol?
- Are they in pain?
- Do they have HF?
- Do they have electrolyte imbalances?
- Do they have renal/hepatic failure?
161
Analgesia
First and second line for neuropathic pain?
- FIRST: Amitriptyline (10 mg ON)
| - Second: Pregablin (75 mg OD 12hrly)
162
Analgesia
First line for diabetic neuropathy?
- Duloxetine
163
What does 1% mean in calculations?
- 1g in 100 mL
OR
- 1g in 100g
164
Which drugs might have different salt/base equivalents? Where to find in BNF?
- Phenytoin
- Digoxin
- Sodium fusidate
Can find this info in dose equivalents and conversion section of drug.
165
Prescriber mnemonic
* P – Patient details
* Re – REaction (allergy plus the reaction)
* S – Sign the front of the chart
* C – check Contraindications to each drug
* R – check Route for each drug
* I – prescribe Intravenous fluids if needed
* B – prescribe Blood clot prophylaxis if needed
* E – prescribe antiEmetic if needed
* R – prescribe pain Relief if needed.
166
Safest antiepileptics in pregnancy?
- FIRST LINE = Lamotrigine
| - Second line = Levetiracetam (caution in depression)
