Lipid lowering drugs Flashcards
1) What is the main general use of statins?
2) Name the 3 statin P-drugs.
1) Primary and secondary prevention of cardiovascular disease.
2) Atorvastatin, Rosuvastatin, Simvastatin.
1) Name 2 vibrates.
2) What is the main use of fibrates?
1) Bezafibrate and Fenofibrate.
2) Hypertriglyceridaemia.
1) Name a specific cholesterol absorption inhibitor.
2) Give 2 uses of this drug class.
1) Ezetimibe.
2) Primary and secondary prevention of CVD and Conn’s syndrome.
Give the 3 main clinical indications for the use of statins and state why they can be used.
1) Primary prevention CVD - prevent CV events in people >40 years old with a 10 year CV risk >20%.
2) Secondary prevention CVD - first line alongside lifestyle changes. To prevent further CV events in those who already have evidence of CV disease.
3) Primary hyperlipidaemia - first line in conditions such as hypercholesterolaemia, mixed dyslipidaemia and familial hypercholesterolaemia.
1) What is the overall effect of statins?
2) What is the mechanism of action of statins?
3) What is the effect of statins on LDL cholesterol?
4) What is the effect of statins on triglycerides and HDL?
1) They reduce serum cholesterol levels. Can also slow the atherosclerotic process, and possibly reverse it.
2) They inhibit HMG-CoA reductase - an enzyme involved in making cholesterol.
3) Decrease cholesterol production by the liver and increase LDL clearance from the blood, reducing levels.
4) Reduce triglyceride levels and slightly increase HDL levels.
1) Name the 2 most common adverse effects of statins.
2) List the adverse of statins on muscles from least severe to most severe effect.
3) List any other side effects of statins.
1) GIT disturbances and headaches.
2) aches > myopathy > rhabdomyolysism (ask patients to report if they start to experience muscle cramps).
3) Rise in liver enzymes such as ALT and drug induced hepatitis.
1) Name 3 types of patients that statins should be usediwth caution in.
2) For use of statins in patients with renal impairment, what should you do?
3) Why should statins not be taken in pregnancy?
1) Patients with existing hepatic impairment, pregnant patients, patients who are breastfeeding.
2) Use a reduced dose as statins are excreted by the kidneys.
3) Because cholesterol is essential for normal foetal development.
1) What types of drugs inhibit statin metabolism?
2) Give 3 examples of these types of drugs.
3) Name another drug which has a similar interaction, but a less clear mechanism.
4) Give 2 possible actions to be taken to avoid adverse effects due to this interaction.
1) cytochrome P450 inhibitors.
2) Amiodarone, Diltiazem, Itraconazole, Macrolides and protease inhibitors.
3) Amlodipine.
4) Reduce the dose of the statin, or if the other drug is being used for a short period of time (antibiotic short course) then withhold the statin for the antibiotic therapt time period.
If a patient is taking simvastatin or atorvastatin, what should they avoid and why?
They should avoid grapefruit juice as this inhibits the cytochrome P450 enzymes, so statin metabolism will be reduced and the risk of side effects will be greater.
1) Why should you check a patients thyroid function before starting a statin?
2) The risk of what increases if statins are prescribed to a patient with hypothyroidism?
1) Because hypothyroidism is a reversible cause of hyperlipidaemia, and so the statin may be unneccessary.
2) Myositis.
Give a basic description of how to monitor patients taking statins for primary and secondary prevention.
For primary prevention, check lipid profile before treatment, but after this, no routine checks requried as no specified target levels need to be reachesd.
For secondary prevention, baseline lipid profile not requried as CVD already established. However, monitor efficacy by checking that target cholesterol levels are achieved.
1) For safety when using statins, what should be checked, and how often should they be checked?
2) What are the guidelines for the safe levels?
1) Liver enzymes should be checked at baseline, 3 months and 12 months.
2) A rise in ALT of up to 3 times the upper limit is acceptable. A rise abvoe this should lead to statin discontinuation.
1) Where does the most important action of statins take place?
2) What is involved in this particular process?
3) Why are short acting statins such as simvastatin more effective when taken at night?
1) the liver.
2) fall in hepatic cholesterol > compensatory upregulation of LDL receptors on hepatocytes > increased clearance circulating LDL cholesterol > in liver, cholesterol processed into bile salts.
3) Because this is the time when most cholesterol synthesis takes place.
1) Where does Ezetimibe act?
2) What does Ezetimibe do?
3) Combining Ezetimibe with what other drug class produces a highly effective combination?
1) Brush border of the small intestinal mucosa.
2) Inhibits the NPC1L1 transporter and revues cholesterol absorption from the gut by about 50%.
3) Statins (Ezetimibe and low dose statin = 3 doubling of the statin dose.
Why does Ezetimibe have a long half life of 22 hours?
Because it undergoes enterohepatic circulation.
