Tell him to go to the regular GP and get a good check up. Tell him to get hormones (like testosterone level) and any other possible health issues checked. Everyone needs to do this every once in awhile anyway. The problem may be mental, but I think it's always good to check on any possible health problems first and then look at mental/emotional.

Down below is something I found online that's kind of interesting....

Notice the first on the list is low testosterone!!! I think you've mentioned that he has always had a low sex drive so that's one thing I'd definitely check on:

>> A study conducted by the Journal of the American Medical Association (JAMA) in February 1999 stated that about 43 percent of women and 31 percent of men suffer sexual inadequacy. Here are some of the possible causes for low libido:
Suboptimal amounts of testosterone in the body
Stress
Not enough sleep
Unresolved conflicts in the relationship
A desire to control or punish spouse
A way to have power over spouse
Sexual orientation conflict or confusion
Anger
Past sexual abuse
Working long hours
Too much alcohol consumption
Male andropause
Cardiovascular disease
Diabetes
Parkinson's disease
Endocrine or neurological disorders
Hypothroidism
Depression
Family worries
Anemia
Arthritis
Chronic pain
Antidepressants
Tranquilizers
Antihypertensive medications
Illegal substances such as heroin, cocaine and marijuana
Infidelity<<
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