Febuxostat Side Effects

Though most gout patients – or at least the ones who read GoutPal.com – understand the importance of lowering uric acid, many are concerned about medication side effects.

To put this into context, the side-effects of NOT lowering uric acid are extensive bone, cartilage, and tendon damage for gout sufferers. This is permanent damage caused by urate crystals, but so slow that you do not notice until it is too late. Another side-effect of high uric acid in the blood is an increased risk of kidney stones. These can cause permanent kidney damage, and they are extremely painful. So, before you dismiss urate lowering therapy for fear of the (often low) risk of side effects, consider carefully the (almost certain) risks of doing nothing.

I’ve written about allopurinol side effects before, but now that we have a new uric acid lowering drug, febuxostat, gout patients are wondering if this has fewer effects.

A clear side-by-side comparison is beyond the scope of this article. There are several comparative studies, but none, as far as I am aware, are a strict comparison of doses at similar uric acid levels.

Febuxostat launched recently in the US under the brand Uloric. Previously, it was launched in Europe under the brand Adenuric. Earlier this month, the European Public Assessment Report for Adenuric was updated, which includes summaries of side effects from trials of febuxostat for gout patients.

Febuxostat Side Effects

The side effects are grouped as Common, Uncommon, and rare. In alphabetical order (within each group), they are:

Common side effects (more than 1 in 100 patients but less than 1 in 10 patients) are:

• diarrhea
• feeling sick
• headache
• liver test results abnormal
• rashes

Uncommon side effects (more than 1 in 1,000 patients but less than 1 in 100 patients) are:

• abdominal pain/discomfort or wind
• abnormal ECG heart tracing
• abnormal frequent urination
• abnormal urine tests (increased level of proteins in urine)
• blood in the urine
• change in blood sugar levels (diabetes) of which a symptom may be excessive thirst, increased blood fat levels
• changes in blood chemistry or amount of blood cells (abnormal blood test results)
• constipation
• cough, shortness of breath, flu-like symptoms
• difficulty in sleeping
• dizziness
• dry mouth
• erectile difficulties and/or loss of sex drive
• fatigue
• impaired sense of taste
• heartburn/indigestion
• hot flushes or blushing (e.g. redness of the face or neck)
• increased appetite
• increased blood pressure
• itching, hives, skin inflammation or discoloration, other type of skin conditions
• kidney stones
• localized swelling due to the retention of fluids in the tissues (edema)
• more frequent passing of stools
• muscle cramp, pain/ache in muscles/joints, bursitis or arthritis (inflammation of joints usually accompanied by pain, swelling and/or stiffness)
• numbness or tingling sensation
• reduction in sensation of touch
• reduction in the ability of the kidneys to function properly
• sleepiness
• vomiting
• weight gain

Rare side effects (more than 1 in 10,000 patients but less than 1 in 1,000 patients) are:

• feeling thirsty
• feeling your heartbeat
• nervousness
• weakness