Gemfibrozil – Uses & Dose

Gemfibrozil – Background

Gemfibrozil belongs to the class of medications called fibrates. Fibrates work by speeding the natural processes that remove cholesterol from the body. They lower the amount of ‘fat’ (triglyceride) and ‘bad cholesterol’ (low density lipoprotein or LDL-cholesterol) as well as increase the amount of ‘good cholesterol’ (high density lipoprotein or HDL-cholesterol) in the blood.

High ‘bad cholesterol’ levels can cause your blood vessels to clog up and lead to chest pain (angina), heart attack or stroke. Hence, fibrates may reduce your risk for heart attack and stroke.

Properties and Characteristics of Gemfibrozil

Drug class	Antilipemic Agents
Brand Names	Lopid
Synonyms	Gemfibrozil, Gemfibrozilo, Gemfibrozilum
Molecular Formula	C15H22O3
Molecular Weight	250.33 g/mol
IUPAC Names	5-(2,5-dimethylphenoxy)-2,2-dimethylpentanoic acid
Structural formula of main components
Pure active ingredient	Gemfibrozil
Appearance	Crystals from hexane
Melting Point	61 – 63 °C
Solubility	In water, 11 mg/L at 25 °C (est)
Excretion	Eliminated in the urine
Available as	Tablets, Granule, Capsule,
Storage	Store gemfibrozil at room temperature between 68°F and 77°F (20°C and 25°C)
Prescription	Prescription is required

What is Gemfibrozil (Lopid) used for?

• Hyperlipidemia
• Hyperlipoproteinemia Type IIb (Elevated LDL + VLDL)
• Hyperlipoproteinemia Type IV (Elevated VLDL)
• Hyperlipoproteinemia Type V (Elevated Chylomicrons + VLDL)
• Hypertriglyceridemia
• Prevention of Cardiovascular Disease

Gemfibrozil side effects

Get emergency medical help if you have signs of an allergic reaction to gemfibrozil: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

In rare cases, gemfibrozil can cause a condition that results in the breakdown of skeletal muscle tissue, leading to kidney failure. Call your doctor right away if you have unexplained muscle pain, tenderness, or weakness especially if you also have fever, unusual tiredness, and dark colored urine.

Also call your doctor at once if you have:

• Sharp pain in your upper stomach (especially after eating);
• Jaundice (yellowing of your skin or eyes);
• Pain or burning when you urinate;
• Blurred vision, eye pain, or seeing halos around lights; or
• Low blood cell counts – pale skin, easy bruising, unusual bleeding, unusual tiredness, feeling light-headed or short of breath, cold hands and feet.

Common gemfibrozil side effects may include:

• Stomach pain, indigestion, diarrhea;
• Numbness or tingly feeling;
• Dizziness, drowsiness;
• Blurred vision;
• Muscle or joint pain; or
• Loss of interest in sex, impotence.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

Mechanism of action

Gemfibrozil activates peroxisome proliferator-activated receptor-α (PPARα), which alters lipid metabolism. This activation leads to increased HDL, apo AI, apo AII, lipoprotein lipase (LPL), inhibition of apo B synthesis, peripheral lipolysis, decreased removal of free fatty acids by the liver, and increased clearance of apoB.

Upregulated LPL reduces plasma triglyceride levels. Decreased hepatic removal of fatty acids decreases the production of triglycerides. The effects on apoB synthesis and clearance decrease VLDL production which also reduce plasma triglyceride levels.

Gemfibrozil’s glucuronide metabolite is also an inhibitor of CYP2C8.

What may interact with this medication?

Do not take this medicine with any of the following medications:

• Bexarotene
• Ezetimibe
• Other cholesterol medicines like clofibrate and fenofibrate
• Repaglinide
• Statin-type cholesterol lowering drugs like atorvastatin, cerivastatin, fluvastatin, lovastatin, pravastatin, or simvastatin

This medicine may also interact with the following medications:

• Warfarin
• Red yeast rice

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

How to take gemfibrozil?

All possible dosages and drug forms may not be included here. Your dosage, drug form, and how often you take the drug will depend on:

• your age
• the condition being treated
• the severity of your condition
• other medical conditions you have
• how you react to the first dose

Drug forms and strengths

Generic: Gemfibrozil

• Form: oral tablet
• Strengths: 600 mg

Brand: Lopid

• Form: oral tablet
• Strengths: 600 mg

Dosage for high cholesterol

Adult dosage (ages 18–64 years):

The typical dosage is 600 mg twice per day.

Child dosage (ages 0–17 years):

It has not been confirmed that gemfibrozil is safe and effective for use in children. Do not use in children younger than 18 years.

Senior dosage (ages 65 years and older):

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This increases your risk of side effects.

If you have kidney problems, your doctor may start you on a lowered dosage or a different medication schedule. This can help keep levels of this drug from building up too much in your body.

Overdosage

If you take too much: You could have dangerous levels of the drug in your body. Symptoms of an overdose can include:

• Stomach upset
• Headache
• Muscle pain

If you think you’ve taken too much of this drug, call your doctor or seek guidance from poison control center.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Blood counts: Rarely, this medication will decrease the number of neutrophils (a type of white blood cell that helps fight infection), red blood cells (which carry oxygen), and platelets (which help your blood to clot). Your doctor will do blood tests to monitor this. If you notice any signs of infection (e.g., fever, chills, or sore throat), fatigue, or unusual bleeding or bruising, contact your doctor as soon as possible.

Gallbladder disease: This medication may increase the risk for gallstones. If you have a history of gallbladder disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Liver function: Liver disease or reduced liver function may cause this medication to build up in the body, causing side effects. If you have liver problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. Your doctor may want to test your liver function regularly with blood tests while you are taking this medication.

If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

Muscle effects: When combined with medications in the HMG-CoA reductase inhibitors class (commonly referred to as “statins”), there is an increased risk of muscle breakdown. If you are taking gemfibrozil and one of these medications, discuss with your doctor how this medication may affect your medical condition, and whether any special monitoring is needed.

If you experience symptoms of muscle breakdown, such as generalized weakness, muscle pain, or a general feeling of being unwell, with or without fever, contact your doctor immediately.

Pregnancy: Strict birth control methods must be used by women who may become pregnant while taking this medication. If you become pregnant despite using birth control, stop taking gemfibrozil and contact your doctor. Women who are planning to become pregnant should stop taking gemfibrozil several months before conception.

Breast-feeding: It is not known if gemfibrozil passes into breast milk. If you are breast-feeding and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of this medication have not been established for children.