Fibrate drugs (drug interactions)

DEFINITION: Drugs used to improve levels of cholesterol and related lipids found in the blood. Fibrates are particularly helpful for persons with high levels of triglycerides.

INTERACTIONS: B vitamins, blood-thinning supplements, statins, bile acid resins, immunosuppressant drugs, some diabetes medications, garlic, ginkgo biloba, red yeast rice, niacin (vitamin B3)

DRUGS IN THIS FAMILY: Clofibrate (Atromid-S), fenofibrate (Tricor), gemfibrozil (Lopid)

B Vitamins

Effect: Possible Helpful Interaction

Fibrate drugs are known to raise homocysteine levels in the blood. High levels of homocysteine have been associated with an increased risk of heart disease, although a direct connection has not been proven.

In a double-blind, placebo-controlled trial of twenty-nine men taking fenofibrate, the use of the B vitamins folate (650 micrograms [mcg]), vitamin B12 (50 mcg), and vitamin B6 (50 milligrams) once daily for six weeks restored homocysteine levels to nearly normal values.

Patients taking fibrate drugs are also advised to avoid niacin (vitamin b3) because it may cause muscle damage.

Blood-Thinning Supplements

Effect: Possible Harmful Interaction

Fibrate drugs are known to increase the blood-thinning effects of drugs in the warfarin (Coumadin) family. Certain herbs, such as garlic, danshen, devil’s claw, dong quai, papaya, and red clover, may thin the blood in a manner somewhat similar to warfarin. Although no such interactions have been reported, it is theoretically possible that the combined use of these herbs and fibrate drugs could pose a risk of bleeding problems. Garlic and ginkgo biloba should also be avoided for this reason. 

Fibrate drugs are also known to interact with certain statins, such as lovastatin and simvastatin. Immunosuppressants, such as ciclosporin or tacrolimus, should not be taken at the same time as fibrate drugs as they may damage the kidneys. Further, women who are pregnant or breastfeeding and patients with diabetes and liver, gallbladder, and kidney conditions should not take fibrate drugs. Should a patient have surgery or dental work scheduled and be taking a fibrate drug, they should alert their medical provider. 

Bibliography

Correa, Ricardo. "Fibrate Medications - StatPearls." NCBI, 1 May 2023, www.ncbi.nlm.nih.gov/books/NBK547756. Accessed 10 Sept. 2024.

Dierkes, J., et al. "Vitamin Supplementation Can Markedly Reduce the Homocysteine Elevation Induced by Fenofibrate." Atherosclerosis, vol. 158, 2001, pp. 161-164.

"Fibrates." Cleveland Clinic, 10 Feb. 2022, my.clevelandclinic.org/health/drugs/22385-fibrates. Accessed 10 Sept. 2024.

Singh, Gauri and Ricardo Correa. "Fibrate Medications - StatPearls." NCBI, 1 May 2023, www.ncbi.nlm.nih.gov/books/NBK547756. Accessed 10 Sept. 2024.