Statin - Simvastatin Flashcards
what is simvastatin used for?
1) primary prevention of CV disease in patients over 40 with a 10 year CV risk
2) secondary prevention of CV disease (1st line alongside lifestyle changes)
3) Primary Hyperlipidaemia ( 1st line in familial or primary hypercholesterolaemia)
How do statins work?
slow atherosclerosis and may reverse it.
Statins reduce serum cholesterol levels by inhibiting HMGb Co A reductase enzymes which make cholesterol.
They also increase clearance of LDL (bad cholesterol) from blood.
reduce triglycerides.
Increase HDL (good cholesterol)
what are the side effects of statins?
- headache
- GI disturbance
Muscle:
- aches
- myopathy
- rhabdomyolysis
- rise in liver enzymes
what are the contraindications of statins?
- hepatic impairment
- renal impairment (statins excreted via kidneys so reduce dose)
- pregnant and breastfeeding (cholesterol needed for fetal development)
What reduced the metabolism of statins?
- cytochrome P450 inhibitors reduce metabolism of statins this leads to accumulation of statins.
- amiodarone
- diltiazem
- itraconazole
- macrolides
what are the drug interactions of statins?
Cytochrome P450 inhibitors reduce metab of statins this leads to accumulation. So reduce the dose of the following:
- amiodarone
- diltiazem
- itraconazole
- macrolides
and amlodipine
what is the typical starting dose of simvastatin in primary prevention?
40 mg daily
what time of day are statins usually taken?
evening
why should patients on statins avoid grapefruit juice?
grapefruit juice inhibits cytpchrome P450 enzymes which metabolise statins —> this leads to accumulation of statins in the body.
why should you check a patient’s thyroid status before starting statins?
Hypothyroidism is a reversible cause of hyperlipidaemia .
Hypothyroidism can cause myositis with statins (inflammtation of muscles)
