Patients should consult their physician before taking any other medication (either prescription or over-the-counter) or nutritional supplements. Of particular concern to patients taking cholesterol reducers are other cholesterol reducers. Taking more than one cholesterol reducer at a time may worsen side effects, unless physicians have prescribed a specially dosed combination of medications.

It is also important to consider the effects of over-the-counter herbal remedies that claim to lower cholesterol. Because these preparations do not make explicit health claims, they do not undergo the same level of scrutiny by the U.S. Food and Drug Administration as do prescription drugs. For example, the herbal remedy “guggul,” derived from the mukul myrhh tree, has been advertised as a “cholesterol-fighter.” However, researchers found, however, that it actually increased levels of LDL (“bad”) cholesterol.

Other substances that may cause concern for some types of cholesterol-reducing drugs include:

Patients taking cholesterol-reducing drugs may also be instructed to avoid grapefruit juice. Grapefruit juice interferes with the liver’s ability to rid the body of some substances. This could lead to a buildup of medications to toxic levels in the body. While the buildup is less likely if the juice is ingested four or more hours prior to the medicine, patients taking cholesterol reducers are usually advised to refrain from drinking grapefruit juice. Patients may also be instructed to avoid eating grapefruit.