LOVASTATIN
Clinical safety rating: avoid
Contraindicated (not allowed)
Competitive inhibitor of HMG-CoA reductase, the rate-limiting enzyme in cholesterol biosynthesis. Reduces hepatic cholesterol synthesis, leading to increased LDL receptor expression and enhanced clearance of LDL from plasma.
| Metabolism | Extensively metabolized in the liver via CYP3A4 isoenzyme. Undergoes first-pass metabolism to active beta-hydroxy acid metabolites. Also metabolized by CYP2C8 and glucuronidation. |
| Excretion | Renal: 10% (as metabolites); Fecal: 83% (primarily as metabolites); Biliary: minor; <5% excreted unchanged in urine. |
| Half-life | Terminal elimination half-life: 1.5–2 hours for lovastatin acid; clinical context: short half-life supports evening dosing to maximize HMG-CoA reductase inhibition during peak cholesterol synthesis. |
| Protein binding | >95% bound primarily to albumin and alpha-1-acid glycoprotein. |
| Volume of Distribution | Vd: 0.3–0.4 L/kg; indicates distribution mainly in extracellular fluid and tissues, with extensive hepatic extraction. |
| Bioavailability | Oral: <5% due to extensive first-pass hepatic metabolism; prodrug (lovastatin lactone) converted to active hydroxy acid in the liver. |
| Onset of Action | Oral: reduction in LDL-C begins within 2 weeks of initiation; full effect observed by 4–6 weeks. |
| Duration of Action | Duration: Effect on LDL-C persists for 24 hours with once-daily dosing; clinical note: maximal effect at trough concentration, sustained with chronic dosing due to inhibition of cholesterol synthesis. |
| Molecular Weight | 404.54 |
10-80 mg orally once daily in the evening, starting at 10-20 mg once daily; maximum dose 80 mg/day.
| Dosage form | TABLET |
| Renal impairment | For severe renal impairment (CrCl <30 mL/min), doses should be limited to 20 mg/day; avoid doses exceeding 20 mg/day. |
| Liver impairment | Contraindicated in active liver disease or unexplained persistent transaminase elevations. For Child-Pugh class A, caution with dose titration; class B or C, avoid use. |
| Pediatric use | For heterozygous familial hypercholesterolemia in patients 10-17 years: start 10 mg orally once daily in the evening, maximum 40 mg/day (dose based on response and tolerability, adjusted at 4-week intervals). |
| Geriatric use | Start at lower end of dosing range (10-20 mg once daily) due to increased risk of myopathy; monitor renal function and adjust if CrCl <30 mL/min (limit to 20 mg/day). |
| 1st trimester | Contraindicated due to risk of fetal skeletal malformations and possible interference with cholesterol synthesis essential for fetal development. |
| 2nd trimester | Contraindicated; crosses placenta and may cause fetal harm. Use only if clearly needed and no safer alternative. |
| 3rd trimester | Contraindicated; theoretical risk of fetal toxicity and interference with postnatal cholesterol synthesis. |
Clinical note
Strong CYP3A4 inhibitors (eg itraconazole) can significantly increase levels and risk of myopathy Can cause myopathy and rhabdomyolysis.
| Placental transfer | Lovastatin and its active metabolite cross the placenta; documented in animal studies and human case reports. |
| Breastfeeding | Excreted into breast milk in low amounts; due to potential for serious adverse effects in nursing infants, breastfeeding is not recommended during lovastatin therapy. |
■ FDA Black Box Warning
None
| Common Effects | Headache |
| Serious Effects |
Active liver diseaseUnexplained persistent elevations of serum transaminasesHypersensitivity to lovastatin or any component of the formulationPregnancyBreastfeeding
| Precautions | Skeletal muscle effects: myopathy, rhabdomyolysis; risk increased with high doses, concomitant use of CYP3A4 inhibitors, fibrates, niacin, or renal impairment., Hepatic effects: elevated transaminases; monitor liver function before initiation and periodically., May increase HbA1c and fasting glucose levels., Avoid use with grapefruit juice due to increased systemic exposure., Use caution in patients with predisposing factors for myopathy (e.g., renal impairment, hypothyroidism, alcohol abuse). |
| Food/Dietary | Grapefruit juice: Consuming >1 quart daily inhibits CYP3A4, increasing lovastatin plasma levels and risk of myopathy. High-fat meals: Enhances absorption; take with evening meal. Avoid concurrent high doses of psyllium or other fiber supplements as they may reduce lovastatin absorption. |
Loading safety data…
| Lactation Rating | L5 (Contraindicated) |
| Teratogenic Risk | Lovastatin is contraindicated in pregnancy due to risk of fetal harm. Statins inhibit HMG-CoA reductase, potentially disrupting fetal cholesterol synthesis necessary for development. First trimester: retrospective data show congenital anomalies (CNS, limb defects) but not significantly elevated; risk may be low. Second/third trimester: theoretical risk persists; no adequate studies. FDA Category X: avoid in pregnant women or those planning pregnancy. |
| Fetal Monitoring | Monitor hepatic function (ALT, AST) before and during therapy, as statins can elevate liver enzymes. Monitor creatine kinase (CK) if muscle symptoms occur, due to risk of myopathy/rhabdomyolysis. In pregnancy if inadvertent exposure, fetal ultrasound to exclude major anomalies. |
| Fertility Effects | No specific human data on fertility effects. In animal studies, no impairment of fertility at clinically relevant doses. However, statins may theoretically alter steroid hormone synthesis; clinical significance unknown. |
| Clinical Pearls | Lovastatin is a prodrug activated in the liver; administer with evening meal to maximize absorption and cholesterol synthesis inhibition (nocturnal). Avoid concurrent use of strong CYP3A4 inhibitors (e.g., itraconazole, ketoconazole, erythromycin, clarithromycin, protease inhibitors, nefazodone) and grapefruit juice (>1 quart/day) due to increased risk of myopathy/rhabdomyolysis. Monitor liver enzymes before initiation, at 12 weeks, and periodically thereafter. Use with caution in patients with predisposing factors for myopathy (renal impairment, hypothyroidism, advanced age). |
| Patient Advice | Take lovastatin with the evening meal to improve absorption and effectiveness. · Avoid drinking large amounts of grapefruit juice (more than 1 quart per day) while on this medication. · Report unexplained muscle pain, tenderness, or weakness, especially if accompanied by fever or malaise. · Do not take lovastatin with certain antifungal, antibiotic, or antiviral medications; inform your doctor of all medications you are taking. · Limit alcohol consumption as it may increase the risk of liver problems. · Maintain a heart-healthy diet low in saturated fat and cholesterol to enhance the drug's effects. · Do not stop taking lovastatin without consulting your doctor, even if you feel well. |