The Pharmaceutical Journal
Vol 273 No 7310 p169-170
31 July 2004

PDF 55K, Acrobat Reader

Society summary

Practice guidance: OTC simvastatin 10mg

Coronary heart disease is the most common cause of premature death in the UK. Following reclassification from prescription-only to pharmacy status, simvastatin 10mg is now available for sale from pharmacies for individuals at moderate risk of CHD. This guidance, prepared in the Royal Pharmaceutical Society's practice division, outlines important points to consider when counterprescribing

There is a correlation between an individual’s serum cholesterol level, (specifically low density lipoprotein (LDL) cholesterol) and the risk of developing coronary heart disease (CHD). Current evidence suggests that adults in western societies may benefit from reducing their serum cholesterol level whatever the baseline level. Serum cholesterol alone, however, is a poor predictor of CHD risk because of other risk factors that contribute to a person’s overall risk profile.

The National Service Framework for Coronary Heart Disease has prioritised those at greatest risk of CHD and the NHS will provide a number of interventions, including lipid-lowering treatment, to all patients who have had an event as well as all those at 30 per cent or greater 10-year CHD event risk (aiming to reduce this to 15 per cent when resources permit).

The target population for pharmacy self-care is those at “moderate” risk (approximately a 1 in 10 to 1 in 7 (10–15 per cent) chance of developing CHD in the next 10 years). It is possible to determine moderate risk through an individual’s self-reported risk factors.

Who to refer to GP

· Men aged 55 or over with a family history of early heart disease plus at least one other risk factor (see “Risk factors for assessing moderate CHD risk” in panel, right).

· People diagnosed with: diabetes; angina; a previous heart attack or stroke; peripheral vascular disease; familial hypercholesterolaemia/hyperlipidaemia; hypertension; liver disease or history of abnormal liver function tests; hypothyroidism; renal impairment; family history of muscle disorders (eg, muscular dystrophies).
· People who have their cholesterol levels measured and the test results indicate a need for referral (fasting LDL-cholesterol level of 5.5mmol/l or greater).

· People who have their blood pressure measured within the pharmacy and the results indicate a need for referral in the context of existing Society practice guidance.

· People who:
— experience unexplained heart/chest pain brought on by exercise or exertion
— drink on average more than recommended levels of alcohol: ie, more than four units alcohol/day (men), or three units alcohol/day (women). (one unit = half pint of beer, one small glass of wine, or one single measure of spirits)
— drink grapefruit juice in large amounts (more than one litre daily).

· People who have taken simvastatin or other cholesterol-lowering medication and report symptoms of:
— myopathy/rhabdomyolysis (unexplained generalised muscle pain, tenderness or weakness not associated with flu, exercise or recent strain or injury)
— liver dysfunction (yellowing of the skin and whites of eyes; itching)
— allergic reaction or new skin complaints

What is the OTC indication/dosage?

Simvastatin 10mg is indicated to reduce the risk of a first major coronary event (non-fatal myocardial infarction and CHD deaths) in people likely to be at moderate risk — a 1 in 10 to 1 in 7 (10-15 per cent) chance of developing CHD in the next 10 years. Simvastatin is given as a single 10mg in the evening and should be taken regularly on a long-term basis.

How does simvastatin work?

Simvastatin competitively inhibits 3-hydroxy-2-methylglutaryl coenzyme A (HMG CoA) reductase, an enzyme involved in cholesterol synthesis, especially in the liver. Simvastatin reduces levels of LDL-cholesterol (the so-called “bad cholesterol”) and increases levels of high density lipoprotein (HDL) cholesterol (sometimes referred to as “good” cholesterol because levels are inversely related to CHD risk). Reductions in LDL-cholesterol correlate closely with reduction in CHD risk.

Cholesterol and blood pressure

Cholesterol testing: It is not essential to know someone’s cholesterol status to identify them as being at moderate risk (see section on “risk factors for assessing moderate CHD risk”). Cholesterol testing is not a prerequisite to selling simvastatin; however, it is good practice to offer a cholesterol test or ascertain a recent cholesterol level when making an initial sale. This is to screen for people with high cholesterol (an initial fasting LDL-cholesterol level of 5.5mmol/l or greater who might require GP treatment) and to establish a baseline level against which to measure progress.

It is good practice to offer a further cholesterol test annually. This may help determine whether the medication is being taken properly and provide encouragement for the individual to continue taking simvastatin.

See also practice guidance on cholesterol testing (PDF 800K).

Blood pressure monitoring: Although it is not necessary to measure blood pressure before starting simvastatin, it is good practice to offer a blood pressure test if this service is available. This is primarily to screen for hypertension that may alter a person’s risk factors and warrant medical treatment.

See also practice guidance on blood pressure monitoring (PDF 190K).

Who should sell OTC simvastatin?

Initial sales: The pharmacist should be involved in all initial sales of simvastatin. They should not delegate this to medicines counter assistants (MCAs), although MCAs may be used to elicit some of the information from the individual. However, the pharmacist should be involved in the counselling of the individual and authorise the sale.

Subsequent sales: It is a matter for professional judgement whether the pharmacist needs to be personally involved in subsequent sales or whether these may be delegated to appropriately trained MCAs. Wherever possible, regular customers should be offered an annual review, covering issues such as changes to risk factors, adverse effects, interactions and compliance. MCAs involved in subsequent sales should check that there have been no changes to the person’s risk factors, adverse effects etc that might warrant referral to the pharmacist.

A questionnaire may be useful to elicit information from the customer and define the suitability of the individual for treatment with simvastatin.

Sales to third parties: It is good practice to make all initial sales directly to the client. Sales to third parties may be considered for subsequent sales provided that the pharmacist/ MCA can establish that the individual’s risk factors, adverse effects etc have not changed.

Contact with local GPs/PCOs

Pharmacists or their representatives (eg, local pharmaceutical committee) need to liaise with their local GPs or primary care organisation to:

· Ascertain any local policies on management of CHD risk and prescribing simvastatin — ie, the local NHS threshold for treatment in the area and how the 15-30 per cent 10-year CHD event risk group are managed.
· Establish local communications, eg, how GPs wish to be informed of purchases of simvastatin or test results should the person consent to sharing information with their GP.
· Agree local policy for referrals.

Pharmacists should consider documenting this information for possible future reference.

Record keeping

It is good practice to record the sale of simvastatin in the PMR, if possible. The individual’s permission should be sought before a record is made. The record will be important in case the individual is prescribed a statin or an interacting medicine in the future. It is also good practice to record if cholesterol/blood pressure tests are offered (with results).

Will OTC simvastatin have any benefits?

Based on evidence from clinical trials with a number of statins at various dosages, simvastatin 10mg is considered likely to confer benefits in terms of reducing CHD events. It may lower LDL-cholesterol by about 27 per cent in practice. However, no specific clinical trials have been conducted with simvastatin 10mg in individuals at moderate risk of CHD.

Contraindications

Hypersensitivity to simvastatin or any excipients; history of muscular toxicity with a statin or fibrate; individuals already taking prescription cholesterol lowering drugs; concomitant administration of potent CYP3A4 inhibitors (eg, itraconazole, ketoconazole, HIV protease inhibitors, nefazodone erythromycin, clarithromycin or telithromycin); active liver disease or unexplained persistent elevations of serum transaminases; pregnancy and breast feeding; women of childbearing potential.

Cautions

Simvastatin 10mg is not intended for those who are known to have existing CHD, diabetes, history of stroke or peripheral vascular disease or familial hypercholesterolaemia. Individuals with these conditions are at higher risk of cardiovascular disease and should be managed under the supervision of a doctor.

Individuals who have been diagnosed as having hypertension are also at increased risk of cardiovascular disease. Therefore, these individuals should consult their doctor before undertaking treatment with OTC simvastatin.

Simvastatin should also be used with caution in those with a history of liver disease or with a high alcohol intake (use should be avoided in active liver disease). See SPC or “Who to refer to GP” (overleaf) for more information.

Adverse effects

The reclassification of simvastatin 10mg tablets to pharmacy status poses no safety concerns that are not already in the SPC. Simvastatin is generally well tolerated; side effects have been usually mild and transient in nature.

Simvastatin may cause abdominal pain, constipation, flatulence, asthenia (weakness or loss of strength) and headache (see SPC).

Muscle effects (myopathy/rhabdomyolysis), liver dysfunction and an apparent hypersensitivity syndrome have been reported rarely. If symptoms indicative of these more serious reactions occur, advise customers that therapy should be discontinued immediately and medical advice sought. Any unexplained allergic symptoms or new skin complaints should be reported back to the pharmacist and/or GP. Pharmacists are reminded to send a yellow card report to the Medicines and Healthcare products Regulatory Agency if a serious adverse drug reaction is suspected.

Drug interactions

Risk of myopathy is increased with concomitant administration of: gemfibrozil and other fibrates; lipid-lowering doses (>1g/day) of niacin (nicotinic acid); ciclosporin; the azole antifungals itraconazole and ketoconazole; HIV protease inhibitors; the antidepressant nefazodone and the macrolide antibiotics erythromycin, clarithromycin and telithromycin. To be on the safe side, any individual on simvastatin who is given any macrolide should be warned to be alert for any signs of myopathy. Simvastatin may modestly potentiate the effect of coumarin anticoagulants and prothrombin time should be determined before starting simvastatin and during early therapy. Pharmacists should advise customers to avoid drinking grapefruit juice. See SPC for full details