Drugs Flashcards
What are P450 enzyme inhibitors?
isoniazid erythromycin sertraline ciprofloxacin acute alcohol intake sodium valproate fluoxetine ketoconazole allopurinol omeprazole fluconazole amiodarone cimetidine ritonavir
What are P450 enzyme inductors?
phenobarbitone chronic alcohol intake carbamazepine rifampicin phenytoin St John's Wort smoking
What are the recommended doses for adrenaline?
< 6 months: 150 micrograms (0.15ml 1 in 1,000)
6 months - 6 years: 150 micrograms (0.15ml 1 in 1,000)
6-12 years: 300 micrograms (0.3ml 1 in 1,000)
Adult and child > 12 years: 500 micrograms (0.5ml 1 in 1,000)
Which drugs cause pulmonary fibrosis?
methotrexate
nitrofurantoin
amiodarone
Dopamine receptor agonists
Which drugs are hepatotoxic?
sodium valproate amiodarone sulfonylureas pioglitazone rifampicin methotrexate phenytoin isoniazid ciclosporin
Which drugs cause bronchospasm?
beta-blockers
adenosine
Which drugs cause hyperkalaemia?
ACE inhibitors amiloride heparin angiotensin II receptor blockers spironolactone ciclosporin
Which drugs cause hypotension?
verapamil isosorbide mononitrate diltiazem levodopa bromocriptine
Which conditions do NSAIDs worsen?
urinary retention
psoriasis
Which drugs cause impaired glucose tolerance?
thiazides, furosemide (less common) steroids tacrolimus, ciclosporin interferon-alpha nicotinic acid antipsychotics (beta blockers slightly)
What are the adverse effects of heparin?
bleeding
thrombocytopenia
osteoporosis and an increased risk of fractures
hyperkalaemia - this is thought to be caused by inhibition of aldosterone secretion
What are rare adverse effects of sulfonlyureas?
Hypoglycaemic episodes Weight gain hyponatraemia secondary to syndrome of inappropriate ADH secretion bone marrow suppression hepatotoxicity (typically cholestatic) peripheral neuropathy Avoided in breastfeeding and pregnancy
Which drugs cause myelosuppression/agranulocytosis?
azathioprine methotrexate phenytoin carbamazepine carbimazole
What are the adverse effects of statins?
Myopathy
Liver impairment
Not to be taken during pregnancy
Macrolides are an interaction
What dose of statins are recommended?
atorvastatin 20mg for primary prevention
increase the dose if non-HDL has not reduced for >= 40%
atorvastatin 80mg for secondary prevention
What are the managements for different situations with warfarin?
Situation Management
Major bleeding Stop warfarin
Give intravenous vitamin K 5mg
Prothrombin complex concentrate - if
INR > 8.0
Minor bleeding Stop warfarin
Give intravenous vitamin K 1-3mg
Repeat dose of vitamin K if INR still too high after 24 hours
Restart warfarin when INR < 5.0
INR > 8.0
No bleeding Stop warfarin
Give vitamin K 1-5mg by mouth, using the intravenous preparation orally
Repeat dose of vitamin K if INR still too high after 24 hours
Restart when INR < 5.0
INR 5.0-8.0
Minor bleeding Stop warfarin
Give intravenous vitamin K 1-3mg
Restart when INR < 5.0
INR 5.0-8.0
No bleeding Withhold 1 or 2 doses of warfarin
Reduce subsequent maintenance dose
What are the contraindications for beta blockers?
uncontrolled heart failure
asthma
sick sinus syndrome
concurrent verapamil use: may precipitate severe bradycardia
Which drugs cause hyponatraemia?
loop diuretics thiazides sodium valproate sulfonylureas carbamazepine
What are the adverse effects of thiazolididiones?
weight gain liver impairment: monitor LFTs fluid retention - therefore contraindicated in heart failure. The risk of fluid retention is increased if the patient also takes insulin increased risk of fractures bladder cancer
Which drugs cause hypertension?
corticosteroids
ciclosporin
combined oral contraceptive pill
