PSA Flashcards
what are the contraindacations for taking Metformin?
chronic kidney disease
recent myocardial infarction, sepsis, acute kidney injury and severe dehydration
iodine-containing x-ray contrast media
alcohol abuse
chronic kidney disease: NICE recommend that the dose should be reviewed if the creatinine is > 130 µmol/l (or eGFR < 45 ml/min) and stopped if the creatinine is > 150 µmol/l (or eGFR < 30 ml/min)
metformin may cause lactic acidosis if taken during a period where there is tissue hypoxia. Examples include a recent myocardial infarction, sepsis, acute kidney injury and severe dehydration
iodine-containing x-ray contrast media: examples include peripheral arterial angiography, coronary angiography, intravenous pyelography (IVP); there is an increasing risk of provoking renal impairment due to contrast nephropathy; metformin should be discontinued on the day of the procedure and for 48 hours thereafter
alcohol abuse is a relative contraindication
what are the adverse effects assoicated with taking metformin?
gastrointestinal upsets are common (nausea, anorexia, diarrhoea), intolerable in 20%
reduced vitamin B12 absorption - rarely a clinical problem
lactic acidosis* with severe liver disease or renal failure
How do Sulfonylureas work?
oral hypoglycaemic drugs used in the management of type 2 diabetes mellitus. They work by increasing pancreatic insulin secretion and hence are only effective if functional B-cells are present. On a molecular level they bind to an ATP-dependent K+(KATP) channel on the cell membrane of pancreatic beta cells.
What are common and rare side effects of sulfoylureas ?
Common adverse effects
hypoglycaemic episodes (more common with long acting preparations such as chlorpropamide)
weight gain
Rarer adverse effects syndrome of inappropriate ADH secretion bone marrow suppression liver damage (cholestatic) peripheral neuropathy
Dipeptidyl peptidase-4 (DPP-4) inhibitors (e.g. Vildagliptin, sitagliptin)
Key points
oral preparation
trials to date show that the drugs are relatively well tolerated with no increased incidence of hypoglycaemia
do not cause weight gain
NICE guidelines on DPP-4 inhibitors
NICE suggest that a DPP-4 inhibitor might be preferable to a thiazolidinedione if further weight gain would cause significant problems, a thiazolidinedione is contraindicated or the person has had a poor response to a thiazolidinedione
What are thiazide common and rare adverse effects?
Common adverse effects dehydration postural hypotension hyponatraemia, hypokalemia, hypercalcaemia gout impaired glucose tolerance impotence
Rare adverse effects thrombocytopaenia agranulocytosis photosensitivity rash pancreatitis
What are loop diuretics adverse effects?
Adverse effects
hypotension hyponatraemia hypokalaemia hypochloraemic alkalosis ototoxicity hypocalcaemia renal impairment (from dehydration + direct toxic effect) hyperglycaemia (less common than with thiazides) gout
What are the Spironolactone Indications?
Indications
ascites: patients with cirrhosis develop a secondary hyperaldosteronism. Relatively large doses such as 100 or 200mg are often used
hypertension: used in some patients as a NICE ‘step 4’ treatment
heart failure (see RALES study below) NYHA III + IV, patients already taking ACE inhibitor low dose spironolactone reduces all cause mortality
nephrotic syndrome
Conn’s syndrome
What are Spironolactone adverse effects?
Adverse effects
hyperkalaemia
gynaecomastia
What is the common dose of: Paracetamol ibuprofen Codeine Co-codamol Co-codamol
Paracetamol 1g qds Ibuprofen 200-400mg tds Codeine 30-60mg qds Co-codamol 8/500 Co-codamol 30/500 2 tabs qds
What is the common dose of: cyclizine Metoclopramide Amoxicillin Clarithromycin
cyclizine 50mg tds
Metoclopramide 10mg tds
Amoxicillin 500mg tds
Clarithromycin 500mg bd
What is the common dose of:
Lansoprazole
Omeprazole
Levothyroxine
Metformin
Lansoprazole 15-30mg od
Omeprazole 20-40mg od
Levothyroxine 25-200mcg od
Metformin 500mg od - 1g bd
What is the common dose of:
Aspirin Clopidogrel Simvastatin Atenolol Ramipril Bendroflumethiazide* Furosemide
Cardiovascular drugs
Aspirin 75-300mg od Clopidogrel 75-300mg od Simvastatin 10-80mg on Atenolol 25-100mg od Ramipril 1.25-10mg od Bendroflumethiazide* 2.5mg od Furosemide 20mg od - 80mg bd** Amlodipine 5-10mg od
What drugs may worsen seizure control in patients with epilepsy?
The following drugs may worsen seizure control in patients with epilepsy:
alcohol, cocaine, amphetamines ciprofloxacin, levofloxacin aminophylline, theophylline bupropion methylphenidate (used in ADHD) mefenamic acid
What drugs cannot be prescribed in pregnant patients?
Antibiotics tetracyclines aminoglycosides sulphonamides and trimethoprim quinolones: the BNF advises to avoid due to arthropathy in some animal studies
Other drugs ACE inhibitors, angiotensin II receptor antagonists statins warfarin sulfonylureas retinoids (including topical) cytotoxic agents
The majority of antiepileptics including valproate, carbamazepine and phenytoin are known to be potentially harmful. The decision to stop such treatments however is difficult as uncontrolled epilepsy is also a risk
