Are there any negative side effects from taking Benadryl?

Yes, there are some negative side effects you may experience while taking Benadryl. Common side effects include feeling sleepy or drowsy or feeling nervous, restless or excitable. Also, you may not be able to take Benadryl or a low dose if you have certain conditions, because the medicine may make them worse. These conditions include:

  • high blood pressure
  • glaucoma
  • thyroid problems
  • enlarged prostate
  • stomach ulcers
  • asthma

If you have any of these conditions, check with your doctor before taking Benadryl. Also, if you are taking or have just taken medications called monoamine oxidase inhibitors in the last two weeks, do not take Benadryl. The combination can cause very dangerous drug interactions and cause severe side effects. There is also a possibility of having an allergic reaction to Benadryl. If you are having any side effects that do not go away, stop taking the medication and call your doctor.  He may be able to direct you to a different medication for your allergy symptoms.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.