lovastatin

Action

Inhibits HMG-CoA reductase, an enzyme crucial to cholesterol synthesis. Decreases total cholesterol and low-density lipoprotein (LDL) levels and increases high-density lipoprotein level.

Availability

Tablets: 10 mg, 20 mg, 40 mg

Tablets (extended-release): 10 mg, 20 mg, 40 mg, 60 mg

Indications and dosages

➣ To reduce LDL, total cholesterol, triglyceride, and apolipoprotein B levels

Adults: Initially, 20 mg P.O. daily. May be increased, as needed, at 4-week intervals to a maximum of 80 mg/day as a single dose or in divided doses. Or 20 mg P.O. (extended-release) daily. May be increased, as needed, at 4-week intervals to a maximum daily dosage of 60 mg.

➣ Heterozygous familial hypercholesterolemia in boys and postmenarchal girls ages 10 and older who have high LDL and cholesterol levels despite adequate trial of diet therapy

Adolescents ages 10 to 17: 10 to 40 mg P.O. daily, with adjustments made at 4-week intervals

Dosage adjustment

• Severe renal insufficiency

Off-label uses

• High-risk patients with diabetic dyslipidemia, familial dysbetalipoproteinemia, familial combined hyperlipidemia, or nephrotic hyperlipidemia

Contraindications

• Hypersensitivity to drug, its components, or angiotensin-converting enzyme inhibitors

• Active hepatic disease or unexplained persistent hepatic enzyme elevation

• Concurrent gemfibrozil or azole antifungal therapy

• Pregnancy or breastfeeding

Precautions

Use cautiously in:

• cerebral arteriosclerosis, heart disease, renal impairment, severe acute infection, severe hypotension or hypertension, uncontrolled seizures, myopathy, visual disturbances, major surgery, trauma, alcoholism

• severe metabolic, endocrine, or electrolyte problems

• women of childbearing age

• children.

Administration

• Give daily dose with evening meal.

• Increase dosage at intervals of 4 weeks or longer, as ordered.

• Don't give with grapefruit juice (may increase drug blood level).

☞ Discontinue if alanine aminotransferase (ALT) or aspartate aminotransferase (AST) level exceeds three times the upper limit of normal.

Adverse reactions

CNS: headache, dizziness, asthenia

EENT: blurred vision, eye irritation

GI: nausea, vomiting, constipation, diarrhea, abdominal pain or cramps, dyspepsia, flatulence

Hepatic: hepatotoxicity

Musculoskeletal: myalgia, cramps, rhabdomyolysis

Skin: pruritus, rash, photosensitivity

Other: hypersensitivity reaction

Interactions

Drug-drug. Azole antifungals, cyclosporine, erythromycin, folic acid derivatives, gemfibrozil, niacin: increased risk of myopathy and rhabdomyolysis

Bile acid sequestrants: decreased lovastatin blood level

Isradipine: increased lovastatin clearance

Warfarin: increased prothrombin time, bleeding

Drug-diagnostic tests. ALT, AST: increased levels

Drug-food. Grapefruit juice: increased lovastatin blood level

Drug-herbs. Red yeast rice: increased risk of adverse reactions

Chaparral, comfrey, germander, jin bu huan, kava, pennyroyal, St. John's wort: increased risk of hepatotoxicity

Patient monitoring

• Obtain liver function tests before starting therapy, 6 and 12 weeks after therapy begins or dosage is increased, and periodically thereafter.

Patient teaching

• Tell patient to take immediate-release tablets with evening meal or extended-release tablets at bedtime.

• Instruct patient not to break, crush, or chew extended-release tablets.

• Emphasize importance of cholesterol-lowering diet and other therapies, such as exercise and weight control.

☞ Instruct patient to report unexplained muscle pain, tenderness, or weakness, as well as signs or symptoms of hepatotoxicity (fever, malaise, abdominal pain, yellowing of skin or eyes, clay-colored stools, or tea-colored urine).

☞ Advise patient to contact prescriber immediately if she is breastfeeding or suspects pregnancy.

• Tell patient not to use herbs without consulting prescriber.

• Inform patient that drug may cause photosensitivity. Caution him to avoid excessive sun or heat lamp light.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, foods, and herbs mentioned above.