The April 2004 issue of the journal Urology published the findings of Italian researchers that the amino acid carnitine was more active than testosterone in improving symptoms of aging in men, such as sexual dysfunction and depression, associated with the decline of androgenic hormones.
One hundred twenty men between the ages of 60 and 74 with symptoms of low testosterone were randomized to receive 160 milligrams orally administered testosterone undecanoate, 2 grams propionyl-L-carnitine plus 2 grams acetyl-L-carnitine per day, or a placebo for a six month period. Prostate-specific antigen, prostate volume, nocturnal penile tumescence, total and free testosterone, prolactin, luteinizing hormone, erectile function scores, depression, fatigue and other parameters were assessed before treatment, at three months, and after the treatment period.
Erectile function, sexual desire, sexual satisfaction and nocturnal penile tumescence increased over the course of the study in the group receiving testosterone as well as the group receiving carnitine. In addition, the group receiving carnitine experienced an increase in orgasm and general sexual well-being. Erectile function and nocturnal penile tumescence were significantly more improved in this group than in those receiving testosterone. While both treatments lowered depression scores, carnitine’s effect was greater.
Predictably, treatment with testosterone increased serum total and free testosterone and decreased luteinizing hormone levels, but carnitine’s effect on these hormones was not significant. Treatment with carnitine was not associated with an increase in prostate volume as was testosterone treatment after six months. PSA levels did not increase in any of the groups.
Fatigue was likewise improved in both groups. As one negative effect, the men taking testosterone developed enlargement of their prostates, which did not occur in the carnitine-treated group. Although both testosterone and carnitine improved symptoms of male aging, there was overall superior benefit to carnitine with no real side effects.
OBJECTIVES: To To compare testosterone undecanoate versus propionyl-L-carnitine plus acetyl-L-carnitine and placebo in the treatment of male aging symptoms.
METHODS: A total of 120 patients were randomized into three groups. The mean patient age was 66 years (range 60 to 74). Group 1 was given testosterone undecanoate 160 mg/day, the second group was given propionyl-L-carnitine 2 g/day plus acetyl-L-carnitine 2 g/day. The third group was given a placebo (starch). Drugs and placebo were given for 6 months. The assessed variables were total prostate-specific antigen, prostate volume, peak systolic velocity, end-diastolic velocity, resistive index of cavernosal penile arteries, nocturnal penile tumescence, total and free testosterone, prolactin, luteinizing hormone, International Index of Erectile Function score, Depression Melancholia Scale score, fatigue scale score, and incidence of side effects. The assessment was performed at intervals before, during, and after therapy.
RESULTS: Testosterone and carnitines significantly improved the peak systolic velocity, end-diastolic velocity, resistive index, nocturnal penile tumescence, International Index of Erectile Function score, Depression Melancholia Scale score, and fatigue scale score. Carnitines proved significantly more active than testosterone in improving nocturnal penile tumescence and International Index of Erectile Function score. Testosterone significantly increased the prostate volume and free and total testosterone levels and significantly lowered serum luteinizing hormone; carnitines did not. No drug significantly modified prostate-specific antigen or prolactin. Carnitines and testosterone proved effective for as long as they were administered, with suspension provoking a reversal to baseline values. Only the group 1 prostate volume proved significantly greater than baseline 6 months after testosterone suspension. Placebo administration proved ineffective. Negligible side effects emerged.
CONCLUSIONS: Testosterone and, especially, carnitines proved to be active drugs for the therapy of symptoms associated with male aging.
Cavallini G, Caracciolo S, Vitali G, Modenini F, Biagiotti G. Carnitine versus androgen administration in the treatment of sexual dysfunction, depressed mood, and fatigue associated with male aging. Urology. 2004 Apr;63(4):641-6.