Question

Allopurinol is used in the treatment of:

• A. Osteoarthritis
• B. Gout
• C. Rheumatoid arthritis
• D. Ankylosing spondylitis

Hint:

Which listed disease is caused by high uric acid?

Answer 1

The Correct Option is B

The key to this question is to follow the uric acid pathway. Allopurinol is a structural analogue of hypoxanthine and it shuts down xanthine oxidase. Because that enzyme is the final step in making uric acid, the result is a fall in serum urate.

Now ask which of the four diseases is driven by uric acid. Only one is. Gout results from urate crystals settling in joints when blood uric acid runs high. A drug that reduces urate production therefore treats and prevents gout, which is exactly why allopurinol is prescribed for it in the chronic setting.

The remaining choices have nothing to do with uric acid. Osteoarthritis is wear-and-tear cartilage loss, rheumatoid arthritis is an immune-mediated synovitis managed with disease-modifying agents, and ankylosing spondylitis is an inflammatory spinal arthritis managed with anti-inflammatories and biologics. None would respond to a xanthine oxidase inhibitor.

So the only disease that fits the drug is gout.
\[\boxed{\text{Gout (option B)}}\]