Randomized crossover trial of amoxapine versus vitamin B12 for retrograde ejaculation

Abstract

Objective To compare the efficacy and safety of amoxapine and vitamin B12 for treating retrograde ejaculation (RE).Materials and Methods Between May 2009 and November 2012, this open-label, randomized, crossover study enrolled 26 men suffering with RE at Department of Reproductive Medicine, Omori Hospital. Patients were randomly allocated into two groups (n=13 each). The amoxapine-B12 group received amoxapine (50 mg daily for 4 weeks, orally) followed (after a 1-week washout period) by vitamin B12 (500 μg three-times daily for 4 weeks). The B12-amoxapine group received the opposite regimen. All patients masturbated to ejaculation at least twice during each treatment period. The primary outcome was antegrade ejaculation of semen, as reported by the patient, on more than one occasion during either treatment period (defined as treatment success). Any adverse events were noted. Success rates were compared between treatments using Fisher’s exact test.Results One patient (B12-amoxapine group) withdrew for personal reasons (breakdown of marital relations); all other patients completed the study. Overall success rate was 88% (22/25). Success rate was higher for amoxapine than for vitamin B12 (80%, 20/25 vs 16%, 4/25; P<0.0001). 18 patients were responsive to amoxapine but not to vitamin B12, 2 patients were responsive to vitamin B12 but not amoxapine, 2 patients were responsive to both drugs, and 3 patients had no response to either drug. One patient (4%) reported sleepiness and 2 (8%) reported constipation while receiving amoxapine. No adverse events were reported during vitamin B12 treatment.Conclusions Amoxapine may be an effective, safe and well-tolerated therapy for RE.

Male Sexual Dysfunctions in the Infertile Couple–Recommendations From the European Society of Sexual Medicine (ESSM)

“… 72 Retrospective cohort 20 men with RE (12 complete, 8 partial) 60mg pseudoephedrine every 6 h on the day before semen analysis and 2 × 60 mg on the day of semen analysis 7/12 (58%) complete RE recovered spermatozoa in an antegrade ejaculate 5/8 partial RE had ≥ 50% increase in antegrade total sperm count 3 Hu et al. 73 RCT 26 men with complete RE (13 in each group) Amoxapine 50mg daily for 4 weeks → 1 week washout → Vit B12 500ug 3 times per day for 4 weeks Crossover to: Vit B12 500 ug 3 times per day for 4 weeks → 1 week washout → Amoxapine 50mg daily for 4 weeks Antegrade ejaculation during treatment: Amoxapine: 20/25 (80%) Vit B12: 4/25 (16%) 2 Kurbatov et al. 74 RCT 24 men with complete RE due to DM1 refractory to Imipramine (12 in each group) Endourethral collagen injection vs. endourethral saline injection Better antegrade volume after collagen injection (mean difference: 0.71ml, P < .05) 2 Arafa et al.…”

“…The tested substances include imipramine (tri-cyclic antidepressant), amoxapine (tri-cyclic antidepressant), B12 vitamin, pseudoephedrine (stimulation of α and β receptors in the urinary tract) as well as injection of collagen within the bladder neck. 72 , 73 , 74 , 75 , 76 One cross-over RCT treated 26 patients with amoxapine (50 mg daily) and B12 vitamin (500 ug 3 times per day), separately for a period of 4 weeks with each drug. 73 Amoxapine, which acts as a noradrenaline re-uptake inhibitor, was effective in 80% of patients compared to only 16% success obtained in the vitamin B12 group.…”

“… 72 , 73 , 74 , 75 , 76 One cross-over RCT treated 26 patients with amoxapine (50 mg daily) and B12 vitamin (500 ug 3 times per day), separately for a period of 4 weeks with each drug. 73 Amoxapine, which acts as a noradrenaline re-uptake inhibitor, was effective in 80% of patients compared to only 16% success obtained in the vitamin B12 group. In another study, comparing the effects of imipramine 25 mg twice per day and pseudoephedrine 120 mg twice per day on RE in diabetic men, Arafa et al.…”

Orgasm and Ejaculation Disorders

“…Several medical approaches have been investigated in order to achieve antegrade ejaculation for natural reproduction in patients with RE. The tested substances include imipramine (tri-cyclic antidepressant), amoxapine (tri-cyclic antidepressant), B12 vitamin, pseudoephedrine (stimulation of α and β receptors in the urinary tract) as well as injection of collagen within the bladder neck [81][82][83][84][85]. One cross-over RCT treated 26 patients with amoxapine (50 mg daily) and B12 vitamin (500 μg three times per day), separately for a period of 4 weeks with each drug [82].…”

“…The tested substances include imipramine (tri-cyclic antidepressant), amoxapine (tri-cyclic antidepressant), B12 vitamin, pseudoephedrine (stimulation of α and β receptors in the urinary tract) as well as injection of collagen within the bladder neck [81][82][83][84][85]. One cross-over RCT treated 26 patients with amoxapine (50 mg daily) and B12 vitamin (500 μg three times per day), separately for a period of 4 weeks with each drug [82]. Amoxapine, which acts as a noradrenaline reuptake inhibitor, was effective in 80% of patients compared to only 16% success obtained in the vitamin B12 group.…”