Lipex

Lipex - Precautions | How to use | Interactions

Lipex is an antihyperlipidemic medication that contains active ingredient called simvastatin. It belongs to a family of drugs called statins or HMG CoA reductase inhibitors. This drug has been studied in many large outcome trials and it has demonstrated many beneficial effects in terms of reducing the risk of heart attack and other complications of the circulatory system. It works by lowering LDL cholesterol up to 47% when used at maximum daily dose (80 mg). It also demonstrated mild increase in levels of HDL cholesterol and mild decrease in levels of apolipoprotein B and triglycerides.

Studies have shown that this drug is actually a chemical derivative of lovastatin (a drug that is also used to lower cholesterol) but is two times more potent than lovastatin.

When administered at a dose of 40 mg once a day, this drug is efficient in the treatment of heterozygous familial hypercholesterolemia because it lowers the level of LDL cholesterol up to 45%.

If applied regularly, Lipex can reduce mortality by 30% in high-risk patients.

Precautions

Clinical studies have shown that the most common side effect is a headache, which is usually mild and last only few days. Other commonly reported adverse effects of Lipex include

  1. diarrhea
  2. constipation
  3. stomach ache
  4. flatulence and dyspepsia

The only serious side effect that has been reported in less than 0.01% of patients is rhabdomyolysis - muscle breakdown and subsequent acute renal failure, which can even endanger the patient's life.

It is, therefore, essential that you see your doctor at the first signs of rhabdomyolysis (muscle cramps, muscle pain and muscle inflammation of unknown cause). It is recommended to regularly control the level of myoglobin in the blood during the first 3 months of therapy.

Lipex can cause mild to moderate liver damage, which is manifested by a transient increase of the enzymes called aspartate aminotransferase and alanine aminotransferase. Severe liver damage in patients who are treated with this drug have also been reported in a very small number of patients. If you notice signs of liver damage, such as: jaundice, pain in the upper right abdomen or severe nausea, you must see your doctor immediately.

Taking of larger doses as well as the concomitant use with other antihyperlipidemic agents increases the risk of rhabdomyolysis and liver injury.

Generally, this drug has an excellent safety profile which is why UK regulatory authorities approved this drug for purchase without a prescription but only for a dose of 10 mg.

Lipex, pregnancy and breastfeeding

AU TGA classifies Lipex in group D because it may cause malformations or irreversible damage to the fetus, and it must not be used during pregnancy.

Cholesterol is important for proper prenatal fetal development and is involved in forming of many tissues in the baby, which is why its consumption during pregnancy is significantly increased. For this reason, use of antihyperlipidemic drugs during pregnancy is not recommended.

It should not be used during breastfeeding because it can affect the metabolism of fat in infants.

How to use

The dose is in the range of 10 - 80 mg once a day depending on the level of LDL cholesterol in the blood.

You should always use the minimum effective dose (lowest dose which reduces cholesterol levels to normal levels) because taking higher doses increase the risk of myopathy and hepatotoxicity. A dose of 80 mg should be used only in patients having a very high risk of a heart attack or stroke.

It is best to take tablet at bedtime, because studies have shown that the efficacy of Lipex is higher at night.

You should not drink grapefruit juice while on treatment with this drug, because grapefruit contains substances that inhibit the CYP3A4 enzyme responsible for the metabolism of Lipex. For this reason, the concomitant use with grapefruit juice significantly increases the concentration of Lipex in the blood and consequently increases the risk of side effects.

Interactions

Lipex should not be taken simultaneously with the following medicines:

  • Cyclosporine (a drug used to prevent rejection of transplanted organs)
  • Calcium antagonists that exhibit an effects in the heart, such as:
  • Nefazodone (an antidepressant). This drug is no longer approved for use in most countries because of its hepatotoxic effects. Co-administration with Lipex increases the risk of severe liver damage.
  • Antibiotics, such as: These drugs are (as grapefruit juice) inhibitors of CYP3A4.
  • Antifungal medications (itraconazole, fluconazole and ketoconazole)
  • Anti-arrhythmics (e.g. amiodarone)
  • Boceprevir - a drug used to treat hepatitis C
  • Medicines to treat AIDS, such as:
  • Danazol
  • Gemfibrozil, clofibrate and fenofibrate - drugs used for lowering triglycerides in the blood.
  • Mifepristone
  • Niacin
  • Colchicine

Side effects

Lipex can cause the following side effects:

  • Tingling
  • Headache
  • Gastrointestinal adverse events (bloating, constipation, diarrhea, nausea, vomiting, abdominal pain, and dyspepsia)
  • Weakness or numbness in hands and feet
  • Itching
  • Alopecia (hair loss)
  • Muscle cramps
  • Muscle pain
  • Inflammation of muscle
  • Muscle weakness
  • Rhabdomyolysis
  • Inflammation of blood vessels
  • Photosensitivity
  • Hepatotoxicity

References

  1. NCBI link 1
  2. NCBI link 2
  3. Patient Information Leaflet