Delayed/retarded ejaculation

  I take daily a significant dose of the antidepressant "Effexor."  For a variety of reasons not germane to the subject I am unable to substitute other antidepressants.  As a result of the medication  I can neither ejaculate nor have an orgasm, even when sex lasts two hours or so.  I readily get and maintain an erection.  A point is reached  when my wife and I get frustrated at what would otherwise appear to be a good thing.  Even if I skip the medication for a couple of days, after an hour or two of sex I finally can ejaculate and have an orgasm,  but obviously that is "less bad" rather than good.  I have tried a half dozen medications known possibly to allieviate the problem, but with no success.  I also take large doses of Wellbutrin and Ritalin on a daily basis for problems unrelated to sex, and despite a reputation for helping to enhance orgasm they have no such benefit.  Now, finally, the questions.  Is Viagra apt to help, and, if so, at what dosage?  Are there any other new medications readily available to allieviate the problem?  I picked up on the Internet reference to anti-nausea drugs adminstered after chemotherapy as being a possibility (albeit expensive).  Do you know anything about this?  Please advise and accept my thanks for any effort on your part.    
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Dear Dan,
Thanks for your question.
Your problem is not one that would be helped by Viagra. This drug will enhance penile blood flow and in those individuals with impotence may enable erections but not enhance or affect orgasms. I am unaware of any medications that will enable orgasms in your situation other than discontinuing/ changing your antidepressant (which you have already tried).
Sorry that I could not offer you more.
This information is provided for general medical information purposes only. Please consult  your physician for diagnostic and treatment options pertaining to your specific medical condition. More individualized care is available through our department at the Henry Ford Hospital  and its satellites (I-800-653-6568).
HFHS M.D.-SAL
*Keyword:sexual dysfunction
hrs:0.25