Benadryl & Prostate Problems

Benadryl is a popular over-the-counter medication that prevents allergy symptoms 1. It is very effective at preventing cough, runny nose and sneezing symptoms. On the other hand, it also has many side effects, including aggravating the symptoms of an enlarged prostate.

Is This an Emergency?

If you are experiencing serious medical symptoms, seek emergency treatment immediately.


The prostate gland is just under the bladder and wraps around the urethra as it enters the bladder. Even though it is closely linked to the urinary system, the prostate gland is also a part of the reproductive system. Its function is to release prostatic fluid containing nutrients during ejaculation. These nutrients give the sperm a better chance at survival inside the vagina, and therefore a better chance of completing fertilization.


Benadryl is a brand name of the drug diphenhydramine HCL 12. It belongs to a group of drugs called antihistamines that block the effects of a substance called histamine, which is released when your body is exposed to allergens. When histamine is blocked, allergy symptoms are prevented 1. It comes in many forms but is usually taken orally. Some common side effects include drowsiness, dry eyes and mouth or dizziness.

Effects on Prostate

Benadryl can also adversely affect your prostate 1. One of the side effects of Benadryl is that it can cause interruption in your pelvic muscles 1. Your prostate is surrounded by pelvic muscles that allow it to contract and release during ejaculation. Benadryl can make these muscles contract more often than release 1. Most people will not notice it at all. However, if you have an enlarged prostate due to infection, abnormal growth or normal aging, this medication can amplify the symptoms you are already experiencing.

Enlarged Prostate Problems

Infection can make the prostate swell. Cancer can cause abnormal growth. Most men also experience benign prostate hyperplasia, or a gradual prostate enlargement, as they age. Whatever the reason your prostate has become enlarged, you may experience symptoms like difficulty urinating or maintaining a strong urine stream. You may also notice burning or pain during ejaculation or urination. Antihistamines worsen these symptoms and can lead to the inability to urinate at all or even more pain.


Men with enlarged prostates should not take Benadryl without consulting their health care provider 1. If your enlarged prostate is caused by infection or unusual growth, your health care provider will treat these conditions first. He will let you know when it safe to use Benadryl again 1. If you have benign prostate hyperplasia, your condition is irreversible. Depending on how severe your condition is, your health care provider will tell you whether it is safe for you to take Benadryl 1. Always follow the directions of your health care provider to avoid complications.