drugs Flashcards
cardiac arrest –> dose of amiodarone
300 mg
amiodarone
Treatment of arrhythmias, particularly when other drugs are ineffective or contra-indicated
Ventricular fibrillation or pulseless ventricular tachycardia refractory to defibrillation (for cardiopulmonary resuscitation)
Statins Adverse effects
myopathy: includes myalgia, myositis, rhabdomyolysis and asymptomatic raised creatine kinase
liver impairment
avoiding statins in patients with a history of intracerebral haemorrhage
Statin contra-indication
macrolides (e.g. erythromycin, clarithromycin) are an important interaction. Statins should be stopped until patients complete the course
pregnancy
statin dose
atorvastatin 20mg for primary prevention
increase the dose if non-HDL has not reduced for >= 40%
atorvastatin 80mg for secondary prevention
Statins should be taken at
night as this is when the majority of cholesterol synthesis takes place. This is especially true for simvastatin which has a shorter half-life than other statins.
ivabradine
Inhibits funny channels so slows pacemaker in SA node
lowers HR
and reduces myocardial O2 demand
used for angina and HF
sacubitril-valsartan
is a Neprilysin inhibitor, inhibits breakdown of natriuretic peptide (ANP, BNP) bradykinin and substance P
this results in increase in diuresis, natriuresis, and vasodilation
used for symptomatic HF with reduced ejection fraction
digoxin
is a cardiac glycoside that increases the force of myocardial contraction and reduces conductivity within AV node
used for AF/flutter and HF
hydralazine
Moderate to severe hypertension (adjunct) Heart failure (with long acting nitrate)
ursodeoxycholic acid
first-line: Primary biliary cholangitis
mechanisms include the improvement of bile acid transport
Dissolution of gallstones
cholestyramine
Bile acid sequestrants act by binding bile acids, preventing their reabsorption; this promotes hepatic conversion of cholesterol into bile acids; the resultant increased LDL-receptor activity of liver cells increases the clearance of LDL-cholesterol from the plasma.
use for: Hyperlipidaemias
Pruritus associated with partial biliary obstruction and primary biliary cirrhosis (for pruritus)
carbimazole
Carbimazole is used in the management of thyrotoxicosis. It is typically given in high doses for 6 weeks until the patient becomes euthyroid before being reduced.
Mechanism of action
blocks thyroid peroxidase from coupling and iodinating the tyrosine residues on thyroglobulin → reducing thyroid hormone production
carbimazole adverse effects
Adverse effects
agranulocytosis
crosses the placenta, but may be used in low doses during pregnancy
propylthiouracil
management of thyrotoxicosis
also has a peripheral action by inhibiting 5’-deiodinase which reduces peripheral conversion of T4 to T3
Verapamil
calcium channel blocker
indications: Angina, hypertension, arrhythmias
Highly negatively inotropic
Verapamil side effects & cautions
Should not be given with beta-blockers as may cause heart block Heart failure, constipation, hypotension, bradycardia, flushing
Diltiazem
calcium channel blocker
indications: Angina, hypertension
Less negatively inotropic than verapamil but caution should still be exercised when patients have heart failure or are taking beta-blockers
Diltiazem side effects & cautions
Hypotension,
bradycardia,
heart failure,
ankle swelling
Nifedipine, amlodipine, felodipine
dihydropyridines
calcium channel blocker
indications: Hypertension, angina, Raynaud’s
Affects the peripheral vascular smooth muscle more than the myocardium and therefore do not result in worsening of heart failure but may therefore cause ankle swelling
Nifedipine, amlodipine, felodipine
(dihydropyridines)
side effects & cautions
Flushing,
headache,
ankle swelling
Metformin side effects
Gastrointestinal side-effects
Lactic acidosis
metformin is associated with an increased risk of lactic acidosis and therefore should be suspended when there is risk eg. dehydration, sepsis, CT with contrast, renal failure, heart failure; particularly if the patient is frail or elderly.
Sulfonylureas (Gliclazide) side effects
Hypoglycaemic episodes
Increased appetite and weight gain
Syndrome of inappropriate ADH secretion
Liver dysfunction (cholestatic
Glitazones side effects
Pioglitazone
Weight gain Heart failure Fluid retention Liver dysfunction Fractures (osteoporosis)
Gliptins side effects
Pancreatitis
Severe lithium toxicity is an indication for
haemodialysis
Adverse effects of heparins include
- bleeding
- thrombocytopenia - see below
- osteoporosis and an increased risk of fractures
- hyperkalaemia - this is thought to be caused by inhibition of aldosterone secretion
Furosemide
inhibits the Na-K-Cl cotransporter in the thick ascending limb of the loop of Henle
Loop diuretics adverse effects
hypotension hyponatraemia hypokalaemia, hypomagnesaemia hypochloraemic alkalosis ototoxicity hypocalcaemia renal impairment (from dehydration + direct toxic effect) hyperglycaemia (less common than with thiazides) gout
Azithromycin prophylaxis is recommended in
COPD patients who meet certain criteria and who continue to have exacerbations
Amoxicillin is usually the first-line antibiotic in the management of
infective exacerbations of COPD.
Atropine
antimuscarinic (anticholinergic)
used to treat the symptoms of low heart rate (bradycardia), reduce salivation and bronchial secretions before surgery or as an antidote for overdose of cholinergic drugs or mushroom poisoning
Never combine B blockers with ..?…. because can increases the risk of cardiovascular adverse effects
Verapamil
b/c used for the treatment of angina, hypertension, and arrhythmias. It is a highly negatively inotropic calcium channel-blocker and it reduces cardiac output, slows the heart rate, and may impair atrioventricular conduction
It may precipitate heart failure, exacerbate conduction disorders, and cause hypotension at high doses and should not be used with beta-blockers.
also Diltiazem is predicted to increase the risk of cardiodepression when given with bisoprolol.
Cimetidine
histamine H₂ receptor antagonist that inhibits stomach acid production
For peptic ulcers
Dabigatran can be reversed by using
idarucizumab
Andexanet alfa
is a recombinant form of factor Xa, used for reversing bleeding in patients taking rivaroxaban or apixaban.
Protamine sulphate
is used as a reversal agent in patients bleeding on heparin, enoxaparin or dalteparin.
Vitamin K is used for reversal of
a raised INR from warfarin
Dabigatran is an oral anticoagulant that works by
being a direct thrombin inhibitor
Carvedilol
is a mixed alpha- and beta-blocker. It is also used for hypertension and angina, as well as playing a role in the management of chronic heart failure
Metoclopramide is a
D2 receptor antagonist* mainly used in the management of nausea. Other uses include:
gastro-oesophageal reflux disease
prokinetic action is useful in gastroparesis secondary to diabetic neuropathy
often combined with analgesics for the treatment of migraine (migraine attacks result in gastroparesis, slowing the absorption of analgesics)
canagliflozin, dapagliflozin and empagliflozin.
are
SGLT-2 inhibitors
SGLT-2 inhibitors side effects
Important adverse effects include
urinary and genital infection (secondary to glycosuria). Fournier’s gangrene has also been reported
normoglycaemic ketoacidosis
increased risk of lower-limb amputation: feet should be closely monitored
Pirfenidone
is an anti-fibrotic. It can be used in idiopathic pulmonary fibrosis.
Minimal glucocorticoid activity, very high mineralocorticoid activity,
Fludrocortisone
Glucocorticoid activity, high mineralocorticoid activity,
Hydrocortisone
Predominant glucocorticoid activity, low mineralocorticoid activity
Prednisolone
Very high glucocorticoid activity, minimal mineralocorticoid activity
Dexamethasone
Betmethasone
Glucocorticoid side-effects
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
Mineralocorticoid side-effects
fluid retention
hypertension
the BNF suggests gradual withdrawal of systemic corticosteroids if patients have: received more than
0mg prednisolone daily for more than one week, received more than 3 weeks treatment or recently received repeated courses
antibiotic for Exacerbations of chronic bronchitis
Amoxicillin or tetracycline or clarithromycin
antibiotic for Uncomplicated community-acquired pneumonia
Amoxicillin (Doxycycline or clarithromycin in penicillin allergic, add flucloxacillin if staphylococci suspected e.g. In influenza)
antibiotic for Pneumonia possibly caused by atypical pathogens
Clarithromycin
antibiotic for Hospital-acquired pneumonia
Within 5 days of admission: co-amoxiclav or cefuroxime
More than 5 days after admission: piperacillin with tazobactam OR a broad-spectrum cephalosporin (e.g. ceftazidime) OR a quinolone (e.g. ciprofloxacin)
antibiotic for Lower urinary tract infection
trimethoprim or nitrofurantoin. Alternative: amoxicillin or cephalosporin
antibiotic for Acute pyelonephritis
Broad-spectrum cephalosporin or quinolone
antibiotic for Acute prostatitis
Quinolone or trimethoprim
Orlistat
a lipase inhibitor, reduces the absorption of dietary fat.
Adjunct in obesity (in conjunction with a mildly hypocaloric diet in individuals with a body mass index (BMI) of 30 kg/m2 or more or in individuals with a BMI of 28 kg/m2 or more in the presence of other risk factors such as type 2 diabetes, hypertension, or hypercholesterolaemia)
120 mg up to 3 times a day, dose to be taken immediately before, during, or up to 1 hour after each main mea
Icatibant
Acute attacks of hereditary angioedema in patients with C1-esterase inhibitor deficiency
tranexamic acid
Prevention and treatment of significant haemorrhage following trauma
Hereditary angioedema
Menorrhagia
Rifaximin
non-absorbable gut specific antibiotic which changes gut flora (Used as second line for Hepatic encephalopathy)
orlistat. It should only be prescribed as part of an overall plan for managing obesity in adults who have:
BMI of 28 kg/m^2 or more with associated risk factors, or
BMI of 30 kg/m^2 or more
continued weight loss e.g. 5% at 3 months
orlistat is normally used for < 1 year
Ondansetron
specific 5HT3-receptor antagonist
for nausea and vomiting
for Moderately emetogenic chemotherapy or radiotherapy
metoclopramide
dopamine antagonist
Symptomatic treatment of nausea and vomiting
Metoclopramide stimulates gut motility
Tamoxifen
is a SERM which acts as an oestrogen receptor antagonist and partial agonist. It is used in the management of oestrogen receptor-positive breast cancer.
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
Anastrozole and letrozole
are aromatase inhibitors that reduces peripheral oestrogen synthesis. This is important as aromatisation accounts for the majority of oestrogen production in postmenopausal women and therefore anastrozole is used for ER +ve breast cancer in this group.
Anastrozole and letrozole Adverse effects
osteoporosis NICE recommends a DEXA scan when initiating a patient on aromatase inhibitors for breast cancer hot flushes arthralgia, myalgia insomnia
icatibant
inhibits bradykinin
for the symptomatic treatment of acute attacks in patients with hereditary angioedema
