Antihistamines - Side Effects

Side effects

Common side effects of antihistamines include drowsiness, dizziness, poor coordination, restlessness, excitability, nervousness, and upset stomach. These problems usually go away as the body adjusts to the drug and do not require medical treatment. Less common side effects, such as dry mouth, nose, and eyes, irritability, difficulty urinating, and blurred vision, also may occur and do not need medical attention unless they do not go away or they interfere with normal activities.

If any of the following side effects occur, check with the physician who prescribed the medicine as soon as possible:

rapid, irregular, pounding, or fluttering heartbeat
convulsions
sweating
vomiting
fever
chills
fainting
breathing problems
hallucinations
unusual bleeding or bruising
low blood pressure
unusual sensitivity to light
uncontrolled movements

Other rare side effects may occur. Anyone who has unusual symptoms after taking antihistamines should get in touch with his or her physician.

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User Comments Add a comment…

5 months ago

Ben Saber » bensaber1 ((at)) hotmail dot com

I took various antihistamines for 15 years one 4 hour pill before bed to help me breath at night. Then one day I decided to stop taking antihistamines. That's when I developped Ulcerative Collitis, an inflammation of my colon. My question is "has there been any study that shows the side effects of quitting antihistamines after a long daily use?" Thank you

8 months ago

white fox » tasmint2 ((at)) aol dot com

sometimes get a very slight numb feeling in my mouth when takeing diphendihydramine

9 months ago

lorna » lirnavie ((at)) yahoo dot com

i am always taking anitihistamine(celestamine,aerius)due to my skin allergies..I started getting very moody,very sensitive emotionally..we always argue with my husband because I cannot deal anymore conversation most especially if talking about problems but the worst thing about it is that these antihistamines that i'm taking don't work for me anymore,it seems like my system is getting used to it now

11 months ago

rafael ortiz » goodchessactor ((at)) yahoo dot com

I have a reaction to antihistamines not found in your lists.

Numbness on the right side of the body.

It started suddenly after using PM medications that contain diphendihydramine over an extended period of time.

I was recently prescribed 2 antianxiety medications that had a histamine for sleep and the reaction became numbness and pain on the right side. This is for your info only. Thanks