Objective: To evaluate the effectiveness and side effects of
amoxapine in treating retrograde ejaculation (RE).
Methods: Totally 25 RE patients who were treated in our
reproduction center were included into this study. The age
ranged from 28 to 54 years old (mean 40.8 years old), and the
duration of RE ranged from 1 month to 25 years (mean 4.5
years). After dividing into 2 groups randomly, 13 patients took
amoxapine 50 mg daily before sleep for 1 month after a washout
period of 1 week; the medication was changed to vitamin B12
500 μg thrice daily after meals for 1 month. The other 12 patients
were placed on the reverse regimen. All patients masturbated at
least twice during each 1-month treatment period. The primary
endpoint was ejaculation of white fluid (semen), as reported by
patients, more than once during a 1-month treatment period.
Results: The total success rate of the two drugs in treating
RE was 88% (22/25 patients). Compared with vitamin B12,
amoxapine was significantly more effective (80%, 20 patients vs.
16%, 4 patients, P<0.0001). Eighteen patients (72%) were cured
by amoxapine only, but failed by vitamin B12. On the other hand,
2 patients (8%) were only responsive to vitamin B12, but not to
Amoxapine. Moreover, 2 patients (8%) were both responsive to
the two drugs, while 3 patients (12%) failed to neither of them.
Only 1 case (4%) was observed sleepiness as the side effect when
Conclusions: Amoxapine is more effective in the treatment of
RE than vitamin B12. The side effects are rare and well tolerated.
Amoxapine may become a promising medicine to treat RE in the