For women with hot flushes who are not able to take hormone replacement therapy (HRT) and especially those who are having treatment for breast cancer, the lack of effective alternative therapies remains a difficult problem. Women taking tamoxifen or aromatase inhibitors will often experience severe vasomotor symptoms, which persist for at least as long as the treatment is continued. The possible role of central neurotransmitters in the causation of the hot flush has prompted randomized, placebo-controlled trials of serotinergic antidepressants, with paroxetine, fluoxetine and venlafaxine demonstrating at least a 50% reduction in flushes, but it is unlikely that these are showing a class effect. However, there are now concerns about the use of paroxetine and fluoxetine, due to their potent inhibition of CYP2D6, which is an essential component in the biotransformation of tamoxifen to the potent antiestrogen endoxifen . So there is an urgent need for alternative treatments in this population.
Citalopram, an antidepressant similar to fluoxetine and paroxetine, is a selective serotonin re-uptake inhibitor (SSRI) that is readily absorbed following oral ingestion, reaching a peak serum concentration in 2–4 hours, and, although it is a weak inhibitor of the CYP2D6 pathway, it does not interfere with tamoxifen metabolism in a clinically significant way. Debra Barton and colleagues have conducted a placebo-controlled trial to evaluate three doses of citalopram (10, 20 and 30 mg) for the treatment of hot flushes . A total of 254 patients were randomly assigned, with a two-to-one chance of receiving active agent compared to placebo, and were studied over 6 weeks. The entry criteria included at least 14 bothersome hot flushes per week. The results showed a significant improvement in hot flushes with citalopram over placebo, with no significant differences between doses. Reductions in mean hot flush scores were 2.0 (23%), 7.0 (49%), 7.7 (50%), and 10.7 (55%) for placebo and 10, 20 and 30 mg of citalopram, respectively ([i]p[/i] ≤ 0.002). Improvement in secondary outcomes, such as the Hot Flush Related Daily Interference Scale, was statistically superior in the 20-mg arm. Citalopram was well tolerated with no significant adverse effects.
Department of Obstetrics & Gynaecology, Heart of England NHS Foundation Trust, Solihull Hospital, Solihull, UK
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