There are only four robustly evidenced and safe non-estrogen interventions for relief from vasomotor symptoms of hot flashes:
- Gabapentin (Neurontin), prescription or OTC (over-the-counter) at 900mg daily (best to build up slowly 300mg each 3 days until reaching 900mg daily, and as there may be some sedative action, entire dose can be taken at nightime, preferably with a meal).
- The SNRI antidepressant venlafaxine (Effexor), at 75mg / daily extended release (prescription item).
- The progestin megesterol acetate, 20mg daily (prescription).
- Tibolone (Livial) (prescription), at 1.25 mg daily.
Of these Livial is the most effective, exceeding the benefit even of HRT, and with demonstrable antitumor benefit, but although approved in 70+ countries, it is currently not available in the U.S. (it would have to be ordered off-prescription from the UK under a personal use FDA exemption). Gabapentin (a natural agent), and Effexor are between at least 40 - 60% effective in general, higher in certain receptive individuals, with megesterol acetate somewhat more effective. Given tolerability, a typical plan of intervention would be to run through trials of (1) gabapentin, (2) Effexor, (3) megesterol, and (4) Livial, in that order, allowing a period of at approximately 6 weeks per trial to judge efficacy (reduction in the number of hot flashes, or in their severity, or both).
Non-agent approaches are switching strategies: switching from tamoxifen to an aromatase inhibitor (AI), or to fulvestrant (Faslodex), or to toremifene (Fareston), as switching is effective in over half of all patients.
Although there are some other miscellaneous options, they are less evidenced and more erratic in benefit, with some safety concerns in some of these, so the above represents the best interventions available to this time.
Breast Cancer Watch