Lovastatin is used together with diet to lower blood levels of "bad" cholesterol (low-density lipoprotein, or LDL), to increase levels of "good" cholesterol (high-density lipoprotein, or HDL), and to lower triglycerides (a type of fat in the blood).

Lovastatin is used to lower the risk of stroke, heart attack, and other heart complications in adults with diabetes, coronary heart disease, or other risk factors.

Lovastatin may also be used for purposes not listed in this medication guide.

You should not use lovastatin if you are allergic to it, or if:

• you are pregnant or breastfeeding; or
• you have active liver disease.

Many drugs can interact and cause dangerous effects. Some drugs should not be used together with lovastatin. Your doctor may change your treatment plan if you also use:

• nefazodone;
• an antibiotic--clarithromycin, erythromycin, telithromycin;
• antifungal medicine--itraconazole, ketoconazole, posaconazole, voriconazole; or
• antiviral medicine to treat HIV or hepatitis C--boceprevir, cobicistat, dasabuvir, elvitegravir, indinavir, lopinavir/ritonavir, nelfinavir, ombitasvir, paritaprevir saquinavir, telaprevir, tipranavir.

Tell your doctor if you have ever had:

• liver disease;
• muscle pain or weakness;
• kidney disease;
• a thyroid disorder; or
• if you drink large amounts of alcohol.

Lovastatin can cause the breakdown of muscle tissue, which can lead to kidney failure. This happens more often in older adults or people who have kidney disease or poorly controlled hypothyroidism (underactive thyroid).

Do not use if you are pregnant. This medicine can harm an unborn baby. Use effective birth control to prevent pregnancy. Stop taking this medicine and tell your doctor at once if you become pregnant.

Do not breastfeed while using this medicine.

Lovastatin is not approved for use by anyone younger than 18 years old.

Use Mevacor (Oral) exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Lovastatin can cause the breakdown of muscle tissue, which can lead to kidney failure. Call your doctor right away if you have unexplained muscle pain, tenderness, or weakness especially if you also have fever, unusual tiredness, or dark colored urine.

Also call your doctor at once if you have:

• muscle weakness in your hips, shoulders, neck, and back;
• trouble lifting your arms, trouble climbing or standing;
• kidney problems--little or no urination, swelling in your feet or ankles, feeling tired or short of breath; or
• liver problems--loss of appetite, stomach pain (upper right side), tiredness, dark urine, jaundice (yellowing of the skin or eyes).

Common side effects may include:

• infections;
• headache; or
• accidental injury.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Avoid eating foods high in fat or cholesterol, or lovastatin will not be as effective.

Avoid drinking alcohol. It can raise triglyceride levels and may increase your risk of liver damage.

Grapefruit may interact with lovastatin and lead to unwanted side effects. Avoid the use of grapefruit products.