The Basics About Fibrates, a Class of Cholesterol-Lowering Drugs

medicine
Wm.Burlingham, istockphoto

Fibrates, also known as fibric acid derivatives, are a class of lipid-lowering drugs that have the ability to affect all aspects of your lipid profile.

The manner by which fibrates lower cholesterol is complex. Fibrates activate a protein called peroxisome proliferator-activated receptor alpha (PPAR-alpha). This protein can activate another enzyme, lipoprotein lipase, which decreases the amount of apolipoprotein C-III in the body.

Ultimately, this results in decreased formation of VLDL and triglycerides and also increases the breakdown of lipids. Fibrates also increase in HDL levels by increasing the amount of apolipoprotein A-I and A-II made in the body. 

There are currently two fibrate drugs approved for use by the Food and Drug Administration (FDA) in the United States:

Fibrates are mostly known for lowering triglycerides and increasing HDL cholesterol. However, they can affect all aspects of your lipid profile. In general, fibrates can:

  • Lower your LDL cholesterol levels by 5 percent to 20 percent.
  • Increase your HDL cholesterol by anywhere between 10 percent to 35 percent.
  • Lower your triglyceride levels by 20 percent to 50 percent.

In order to effectively improve your lipid profile, fibrates can be taken alone or in combination with other lipid lowering agents, such as statins or omega-3 fatty acids.

How You Should Take a Fibrate

You should take your fibrate exactly as prescribed by your healthcare provider and you should be sure not to miss any doses. All fibrate medications are available in a tablet form and are taken by mouth.  Although you can take both types of fibrates with or without food; however, studies have shown that taking the fibrate, gemfibrozil, with a meal helps to increase its absorption.

You should also make sure not to miss any of your appointments with your healthcare provider, since he or she will need to monitor whether or not the medication is working for you. Your healthcare provider may need to make adjustments in your lipid-lowering therapy, depending on how you respond to the drug. While taking fibrates - or any other lipid-lowering therapy - you should also be closely following a diet to lower your cholesterol and triglycerides.

Are There Any Side Effects You Should Look For?

Although fibrates are well-tolerated among people taking them, you may experience some side effects from taking them, The most common side effects noted include experiencing gastrointestinal issues, such as nausea, diarrhea, and abdominal pain. These side effects are usually mild and, in most cases, go away after starting your fibrate.

In some cases, fibrates may increase your liver enzymes, so in addition to your lipids, your healthcare provider will also monitor your liver enzymes periodically.

If you have gallbladder disease, you should let your healthcare provider know, since there is a slight risk of developing gallstones while taking a fibrate. Fibrates may also cause a condition referred to as rhabdomyolysis. Although rare, the risk of developing this condition while taking fibrates increases if you are taking other certain medications along with your fibrate or have certain medical conditions.

Fibrates can increase your likelihood of experiencing a bleed if you are taking a blood thinner, such as Coumadin (warfarin). Because of this, your healthcare provider may adjust your dose while taking fibrates.

The side effects experienced by fibrates are typically mild, but should be brought to your healthcare provider’s attention if they become bothersome or persist for a period of time. You should let your healthcare provider know of any medications you are taking - including any herbal or over-the-counter products - or medical conditions that you have so that he or she can monitor you closely during therapy.

Sources:

Dipiro JT, Talbert RL. Pharmacotherapy: A Pathophysiological Approach, 9th ed 2014.

Malloy MJ, Kane JP. Agents Used in Dyslipidemia. In: Katzung BG, Trevor AJ.eds. Basic & Clinical Pharmacology, 13eNew York, NY: McGraw-Hill; 2015.

Continue Reading