Simvastatin

What Does Simvastatin Do?

Simvastatin is a prescribed medication, mainly used for lowering blood cholesterol levels thus aiding in the prevention and treatment of cardiovascular diseases such as atherosclerosis. Furthermore, it's noted for its anti-inflammatory properties, potentially used in treating conditions like rheumatoid arthritis and slowing Alzheimer's disease and Parkinson's disease progression.

How Does Simvastatin Work? (the complicated stuff)

This drug inhibits the 3-hydroxy-3-methylglutaryl-coenzyme A reductase, an enzyme involved in cholesterol production. The inhibition leads to decreased cholesterol fabrication resulting in an increase in LDL, "bad cholesterol," receptors on liver cells. These receptors extract excess LDL from the bloodstream, thus, reducing overall cholesterol levels. Moreover, simvastatin has anti-inflammatory qualities that reduce the synthesis of isoprenoids, contributing to its preventative role in cardiovascular diseases.

Drug Type and Category of Simvastatin

Simvastatin is a cholesterol-lowering drug, categorised within the statin class of medications.

What dosage of Simvastatin should you be taking?

NICE Guidelines ²

Initially 20–40 mg once daily, taken at night, then increased if necessary up to 80 mg once daily, taken at night, adjusted at intervals of at least 4 weeks. ² The 80 mg dose should only be used in patients who have been taking this dose chronically (e.g. for 12 months or more) without evidence of muscle toxicity. 2,3

For patients with homozygous familial hypercholesterolemia, the typical dose is 40 mg orally once a day. 3

The maximum recommended dose is 80 mg/day, but this higher dose should be used with caution due to an increased risk of myopathy. ³ The dosage may need to be adjusted based on individual response, other medications being taken, and the presence of any liver or kidney disease. ¹

What are the side-effects of Simvastatin?

The most common side effects of simvastatin are:

• Joint and muscle pains (this is very common)
• Cold symptoms like stuffy or runny nose, sore throat, and cough
• Headache
• Stomach pain
• Constipation
• Nausea

Serious side effects that require immediate medical attention include:

• Unexplained muscle pain, tenderness, weakness or cramps, which can also be signs of muscle breakdown and kidney damage
• Yellowing of the eyes or skin, dark urine, and pale stools, which can indicate liver problems
• Severe allergic reactions with symptoms like swollen lips, tongue or throat, trouble breathing, and skin rashes
• Severe stomach pain, which can be a sign of pancreatitis

Other rare but serious side effects are:

• Rhabdomyolysis (muscle breakdown) that can lead to kidney failure
• Liver toxicity
• Severe anemia
• Severe allergic reactions with fever and trouble breathing

Simvastatin can also interact with certain other medications like diltiazem, amiodarone, and grapefruit juice to increase the risk of muscle injury and kidney problems. Drinking large amounts of alcohol while taking simvastatin may cause liver damage.

Drug Interactions

Other Cholesterol-Lowering Drugs:

• Gemfibrozil: Increases the risk of myopathy/rhabdomyolysis.
• Niacin: Can also increase the risk of myopathy/rhabdomyolysis.
• Fibrates: Similar risk as with gemfibrozil and niacin.

Certain Antibiotics and Antifungals:

• Erythromycin and Clarithromycin: Increase simvastatin blood levels, raising the risk of myopathy/rhabdomyolysis.
• Itraconazole, Ketoconazole, Posaconazole: Strong CYP3A4 inhibitors that can significantly increase simvastatin levels.

HIV and Hepatitis C Protease Inhibitors:

• Ritonavir, Saquinavir, Telaprevir, Boceprevir: Can increase the risk of severe muscle problems.

Calcium Channel Blockers:

• Verapamil, Diltiazem, Amlodipine: Can increase the blood levels of simvastatin, leading to a higher risk of myopathy.

• Grapefruit juice contains compounds that inhibit CYP3A4, leading to increased levels of simvastatin in the blood.
• Warfarin: Simvastatin can enhance the effects of warfarin, increasing the risk of bleeding.
• Amiodarone: Can increase simvastatin blood levels, heightening the risk of muscle damage.
• Colchicine: When taken with simvastatin, it can increase the risk of myopathy.
• Cyclosporine: Increases the risk of myopathy/rhabdomyolysis when used with simvastatin.

Natural Alternatives to Simvastatin

Red Yeast Rice: Red yeast rice contains monacolins, which can inhibit the production of cholesterol in the body, similar to how statins work. Studies have shown red yeast rice can reduce total cholesterol and LDL ("bad") cholesterol levels. ⁴

Omega-3 Fatty Acids: Omega-3s found in fish oil have been shown to lower triglyceride levels and potentially raise HDL ("good") cholesterol. Prescription omega-3 medications like icosapent ethyl are recommended for individuals with very high triglycerides. ⁶

Niacin (Vitamin B3): Niacin is a supplement that primarily boosts HDL cholesterol levels. When used with statins, niacin may help further reduce cardiovascular risks. ⁶

Other Supplements: Some studies suggest supplements like garlic, fiber (psyllium), fenugreek, artichoke leaf extract, and berberine may also have cholesterol-lowering effects, though the evidence is less conclusive. 5

Interesting facts about Simvastatin

Simvastatin was developed by Merck & Co. and was first approved for use by the FDA in 1991. It is a synthetic derivative of a fermentation product of Aspergillus terreus.

It is typically taken once daily in the evening, as cholesterol synthesis in the liver is higher at night.

Beyond cholesterol lowering, Simvastatin may have other beneficial effects, such as improving endothelial function, reducing inflammation, and stabilising atherosclerotic plaques.

Disclaimer

This article is generated for informational purposes only. It was created in December 2024. Medications and medical guidance can change over time. Therefore, it is essential to consult with your general practitioner or healthcare provider before making any decisions regarding medications or treatment plans. Your GP can provide personalised advice based on your specific health needs and conditions.

References:

1. https://www.nhs.uk/medicines/simvastatin/how-and-when-to-take-simvastatin/
2. https://cks.nice.org.uk/topics/hypercholesterolaemia-familial/prescribing-information/statins-atorvastatin-rosuvastatin-simvastatin/
3. https://www.drugs.com/dosage/simvastatin.html
4. https://www.healthline.com/health/high-cholesterol/natural-statins
5. https://www.webmd.com/cholesterol-management/high-cholesterol-alternative-therapies
6. https://www.medicinenet.com/what_is_the_best_alternative_to_statins/article.htm