Answer to Question #281876 in Biochemistry for Picklerabbit

Question

What is gout? What are the typical medications used to (a) PREVENT and (b) TREAT gout patients. Explain the mechanisms and side effects of these medications from a biochemist point of view.

Answer 1

When the body breaks down purine-like compounds, uric acid is produced. Purines are a type of amino acid that is naturally created by the body and can also be present in some foods and beverages. Liver, anchovies, mackerel, dry beans and peas, and beer are examples of foods high in purines.

The majority of uric acid is dissolved in the bloodstream and then transported to the kidneys. It then goes through the kidneys and is eliminated by the urine. A person can become ill if their bodies create too much or do not remove enough uric acid. Hyperuricemia is defined as a high uric acid level in the blood.

Gout is an arthritic condition that is extremely painful. Sharp crystals can form in the big toe or other joints if the body has too much uric acid, resulting in gout attacks, which are episodes of swelling and agony. Gout can be managed with medication and dietary and lifestyle modifications.

Typical medications used to prevent gout are:

• Allopurinol is a drug that is taken as a tablet.
• Febuxostat is a drug that is taken as a pill.
• Pegloticase is administered as an intravenous (venous) infusion.
• Probenecid is a tablet that can be consumed.

Typical medications used to treat gout are:

• The use of nonsteroidal anti-inflammatory drugs (NSAIDs) can help to reduce discomfort and swelling. Some people can't take NSAIDs because they have kidney illness, stomach ulcers, or other health issues.
• If taken within 24 hours of a gout episode, colchicine can help reduce inflammation and pain. It is administered orally.
• Pain and swelling can be reduced with corticosteroids. Steroids can be given orally or by injection.

Allopurinol is metabolized in the liver, where it becomes oxypurinol, a pharmacologically active metabolite. Allopurinol has a half-life of 1 to 2 hours, while oxypurinol has a half-life of roughly 15 hours. Both allopurinol and oxypurinol are eliminated by the kidneys. Both allopurinol and oxypurinol block xanthine oxidase, a purine catabolism enzyme that transforms hypoxanthine to xanthine and thereafter to uric acid.

Allopurinol is a relatively safe medicine, yet it can have side effects. There is an increased risk of acute gouty flares due to the destabilization of intra-articular uric acid microtophi upon starting any urate-lowering medication, especially in the first few months. To avoid this, patients should begin taking an anti-inflammatory medicine such colchicine, NSAIDs, or low-dose prednisone (only in patients who cannot take colchicine or NSAIDs) before or at the same time as starting allopurinol.