Simvastatin belongs to the statin class of pharmaceuticals. It is mainly used to lower elevated cholesterol, triglycerides and LDL (low-density lipoproteins, or the so-called “bad” lipoproteins). The drug also increases HDL (high-density lipoproteins or the so-called “good” lipoproteins). These effects help to prevent or even reverse coronary artery disease.
Simvastatin can be prescribed to patients with coronary artery disease, diabetes mellitus, peripheral vessel disease, and a history of cerebrovascular disease (stroke) who have high levels of blood fats to reduce the risk of mortality by reducing the death caused by coronary artery disease, reducing nonfatal myocardial infarction (heart attack) and stroke incidence, and reducing the necessity of coronary and noncoronary revascularization procedures. Simvastatin can also be used by young people suffering from familial (heritable) hypercholesterolemia.
According to clinical studies, only about 1.4% of patients using Simvastatin can experience side effects.
The most common side effects of Simvastatin are:
- Weakness (asthenia)
- Lack of energy
- Headache (usually slight)
- Runny or stuffy nose
- Upper respiratory infections
- Abdominal pain
- Diarrhea or constipation
Taking of Simvastatin less often can still cause such adverse effects as:
- Joint pain
- Muscle cramps
- Muscle aches
- Hepatitis (usually cholestatic that can manifest in itching skin, pale stools and jaundice)
- Difficulty breathing or swallowing
- Persistent sore throat
- Fast or irregular heartbeat
- Shortness of breath
- Swelling of the legs
- Spinning sensation
- Memory loss
- Sensitivity to light
- Infections of the urinary tract
- Impotence (decreased sexual ability)
- Breast development in boys (gynecomastia)
- Worsening of cataracts
- Diabetes mellitus
Apart from the side effects mentioned above, patients using Simvastatin may experience allergic reactions such as anxiety, rash, hives, itching, anaphylaxis and angioedema that can manifest in the form of breathing difficulty, chest tightness, swelling of the mouth, face, lips, or tongue, unusual hoarseness.
Serious side effects
Rhabdomyolysis – breakdown of muscles – is the most serious and dangerous side effect of Simvastatin. This adverse effect mostly occurs when Simvastatin is mixed with different other drugs. When Rhabdomyolysis occurs, the muscle proteins run into the bloodstream and this can lead to kidney failure (sometimes fatal) if there is no urgent medical help. Muscle breakdown manifests in the form of muscle pains, dark-colored urine, weakness, stiffness and myoglobinuria.
Simvastatin can also cause muscle damage (myopathy). Usually it occurs during an overdose. Symptoms of this condition include muscle cramps, stiffness, spasms, tenderness, and general weakness.
In addition, cirrhosis of the liver can also develop. This causes serious liver damage and can be fatal. Clinical presentations include fatigue, loss of appetite, jaundice, itching of skin, and a tendency to bruise easily.
Changes in laboratory tests
Simvastatin can cause positive ANA and can elevate liver enzymes. So keep in mind that Simvastatin may cause such changes as increase in alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and γ-glutamyl transpeptidase. This drug can also lead to an increase in the the level of creatine kinase noncardiac fraction.
During Simvastatin intake, hematological tests can reveal such changes as hemolytic anemia, increased ESR, thrombocytopenia, and leukopenia. Thrombotic thrombocytopenic purpura can also develop.
All these changes are reversible when Simvastatin is discontinued in proper time.
Rare side effects
Using of Simvastatin less often can still cause such side effects as skin changes (eczematous, pruritic rash, erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis, alopecia, nodules, discoloration, dryness of skin/mucous membranes, changes to hair/nails), neurogical problems (paresthesias, peripheral neuropathy, and peripheral nerve palsy), psychiatric changes (suicidal thoughts, delusions, paranoia, and agitation), rheumatoid manifestations (lupus-like syndrome, polymyalgia rheumatica, and vasculitis ophthalmoplegia depression), testicular pain, bilateral leg compartment syndrome, myonecrosis eczematous, thyroid function abnormalities.
It has also been shown that Simvastatin can sometimes induce tumor growth especially in the liver, thyroid, and lung adenomas and carcinomas.
Side effects in pregnant women
Simvastatin is contraindicative to pregnant women because it can cause harm to the fetus, and breast-feeding mothers should not use it as well.
Side effects in children
In children and adolescents (10 to 17 years old), the most common side effects of Simvastatin are headache, abdominal pain and nausea. Incidence of the other adverse effects is the same as in adults. Children younger than 10 years should not use this medicine.
You may never experience any of the side effects listed above. Your doctor cannot predict your body’s reaction to Simvastatin until you have tried it. That is why you should immediately inform your doctor of any changes in your health condition after taking Simvastatin. Therefore, when you feel something is wrong, ask your doctor for advice and he or she will diagnose if your problem is connected with the medicine intake. You should also be careful because some of the side effects of Simvastatin require urgent medical attention.