QUESTION: dr leslie,i am 79 year old male.i have no problem urinating,but i take flomax to relax my muscle.wonder if taking 4 benadryl total 200mg a week is taking a chance  fordifficult urination

ANSWER: Howard:

Most of the time, patients with BPH who are under treatment with Flomax can safely take benadryl.  However, since I am not your treating physician, I can only ask you to pose this question to your regular physician before starting it.

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QUESTION: my pharmacist said people who have kidney  reduction and  prostate  enlargement they can take zyrtec,which is  milder then benadryl and allegra and wont cause urinary retention


All of the anti-histamines mentioned have been associated with urinary retention to some degree.  In one study of 26,000 men taking zyrtec, 96 reported urinary retention which is a small number.  Similar numbers apply to allegra but benadryl is generally associated with much higher percentages of such problems.  


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Stephen W. Leslie, MD


Questions concerning erectile dysfunction, kidney stones and prostate disorders including prostate cancer. I have a special interest in kidney stone disease prevention.


Full time practicing urologist with 30 years experience. Associate Professor of Surgery and Chief of Urology at Creighton University Medical Center. Editor in Chief of eMedicine Urology internet textbook. Author of only NIH approved book written for patients by a urologist on the subject of kidney stones "The Kidney Stones Handbook". Inventor of the "Parachute" and "Escape" kidney stone baskets and the "Calculus" stone prevention analysis computer program.

American Urological Association, Ohio State Medical Association, Sexual Medicine Society

Men's Health, Journal of Urology, Urology, Healthwatch Magazine, Emergency Medicine Monthly, eMedicine, "The Kidney Stones Handbook", and numerous articles in various newspapers. He is also the editor of the Urology Board Review by McGraw-Hill used by urologists to study for their Board Certification Examinations.

Graduate of New York Medical College with residencies completed at Metropolitan Hospital New York, Albany Medical Center and University of Wisconsin-Madison.

Awards and Honors
Thirlby Award of the American Urological Association. Rated as one the country's Best Urologists by the Independent Consumer's Research Institute

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