The fibrates are a type of amphipathic carboxylic acids, belonging to the class of drugs used to lower serum cholesterol levels. They are currently the most important class of drugs combating the worldwide epidemic of atherogenic dyslipidemia. Statins help reduce the levels of low-density lipoprotein cholesterol (LDL) but do not have much effect on serum triglyceride or HDL levels, where the use of fibrates is required. Research shows that the effects of different fibrate medications, while essentially being the same, also differ slightly with regards to their impact on glucose metabolism, insulin resistance, intermittent claudication, microvascular effects of diabetes mellitus; this provides the option of tailoring therapy as per the needs of every patient. The FDA approved indications of fibrates include :
A non-FDA-approved use of fibrates is primary biliary cholangitis.
Fibrates work by a combination of the following mechanisms to cause their hypotriglyceridemic effects:
Fibrates also work to increase high-density lipoprotein (HDL) levels by upregulating the production of Apo-AI and apo-AII in the liver.
Before starting fibrate therapy, patients should start on an adequate lipid-lowering diet. It should be used only as an adjunct to lipid-lowering diet and medication and not as a first-line mode of therapy.
Fibrates are administered orally, ideally as once a day tablets. According to the FDA, the dosing of fibrates in adults is as follows, adjusted for the patient profile :
The above regime is for fenofibrate, which is available as 40 mg and 120 mg tablets. The patient's response to it must be measured every 4 to 8 weeks, followed by adjusting the drug dosage.
The following is a list of adverse effects of fibrates:
The contra-indications to the use of fibrate therapy are:
Fibrates are usually safe drugs that do not need routine monitoring except in the following cases:
Managing appropriate drug use requires free-flowing and efficient communication between an entire interprofessional team, including physicians, nurses, and pharmacists. The same applies to the use of fibrates. Health professionals should bear in mind the adverse outcome of fibrates with regards to liver function tests (LFTs) and ensure that there is regular testing, especially if the patient has pre-existing liver disease. Fibrates are also notorious for causing drug interactions, and health professionals should be thorough with the patient's medication history before prescribing them. If a patient is already on statins, monitor carefully for the development of myopathies, evaluate clotting studies for those on anticoagulants, etc. Most importantly, it is the responsibility of healthcare providers to counsel the patients about the adverse effects of this drug and to ensure they report any new or untoward symptoms(for example- muscle cramps, abdominal pain, indigestion, etc.) after initiating the drug.
An interprofessional team effort is necessary to accomplish the above. The clinician will make the decision to initiate fibrate therapy based on the case facts before them. Still, they would do well to include a pharmacist who can review the patient's current medications to check for possible drug interactions, and verify appropriate dosing. The pharmacist can also assist in choosing a specific fibrate depending on the patient's particular parameters. Nursing should be aware of the signs of the most common interactions and adverse effects; they can check on patient compliance and monitor for adverse events, alerting the prescriber when appropriate. In this way, fibrate therapy can achieve the best possible result with minimal chance of encountering adverse effects. [Level V]
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