Drug products: Allopurinol Nordic Drugs, Allopurinol Orion, Allopurinol Sandoz, Allopurinol Takeda, Allopurinol Teva, Zyloric®
ATC code: M04AA01
Gout is more prevalent in men and more men have been included in clinical studies making statistical meaningful comparison of effect between men and women difficult. Studies have shown women on allopurinol treatment to have more cutaneous hypersensitivity reactions and men to have a higher risk of fractures.
In our opinion, the described differences do not motivate differentiated dosing or treatment in men and women.
Women have far lower prevalence of gout compared with men, the sex difference decreases with increasing age, but men still outnumber women with gout, even among the elderly . A retrospective analysis of hyperuricemic gout patients (3 875 men, 226 women) compared the characteristics of women and men with gout. Women with gout were older and had significantly higher rates of cardiovascular, metabolic and renal comorbidities than the men .
A pharmacokinetic study (10 men, 9 women) aiming to study difference between young and old participants found no difference in pharmacokinetic variables between men and women .
No published placebo-controlled studies with a clinically relevant sex-analysis of the effects of allopurinol have been found. A retrospective analysis of pooled data from three studies comparing febuxostat and allopurinol (3875 men, 226 women) showed better effect of febuxostat , similarly to the overall results from the studies [4-5].Although specific risk factors (e.g. diuretics) are more common for women than for men, a recent review states that there is no evidence that treatment responses differ between men and women .
In the retrospective analysis of pooled data from three studies comparing febuxostat and allopurinol (3,875 men, 226 women) mentioned earlier, similar frequencies of adverse effects were found in the female cohort compared to the entire cohort (including both men and women) .
A large nationwide population-based register study of Taiwanese adults investigated the incidence of, risk factors for, and mortality associated with allopurinol hypersensitivity in new users (360 652 men, 135 211 women). Risk factors for hypersensitivity included female sex, age 60 years or older, initial allopurinol dosage exceeding 100 mg/day, renal or cardiovascular comorbidities, and use for treating asymptomatic hyperuricemia .
In a study of patients with cutaneous adverse drug reactions in a dermatology ward in a Chinese hospital (247 men, 487 women), allopurinol was the most common single drug associated with any type of cutaneous reactions. In the entire study, female patients outnumbered male patients, although patients with severe reactions were more likely to be male .
The risk of fracture from allopurinol use was found to be higher in men in a nationwide Danish registry study (58 072 men, 27 967 women) .
Regarding teratogenic aspects, please consult the Drugs and Birth Defects Database (in Swedish, Janusmed fosterpåverkan).
Date of litterature search: 2017-01-04
Reviewed by: Mia von Euler
Approved by: Karin Schenck-Gustafsson