Q. I overdosed on Benadryl and I feel lightheaded. When will I feel normal?

Answered by
Dr. Seikhoo Bishnoi
and medically reviewed by iCliniq medical review team.
This is a premium question & answer published on Jul 12, 2018 and last reviewed on: Oct 05, 2020

Hello doctor,

I am a healthy 15 year old male. It has been two weeks since I overdosed on Benadryl and I still feel lightheaded and everything is like a dream.

The dose I had taken was 500mg. I also get random confusion spells. When will I feel normal?



Welcome to icliniq.com.

  • Benadryl consists of Diphenhydramine and the drug is an antihistaminic drug.
  • In high doses it causes side effects like blurred vision, dry mouth, confusion, delirium, severe sedation etc.
  • In very high doses this may result in death also. So, I would advise you to please avoid overdose in future. 
  • Usually the toxicity symptoms reduce in about a week and individuals recover, but mild form of toxicity symptoms like confusion, drowsiness, dizzy feeling, restlessness etc., may persist even for up to 4 weeks.
  • So, try to relax yourself, such episodes of restlessness may occur for some time.
  • If symptoms are causing impairment in functioning, then low dose anti-anxiety drugs like Benzodiazepines as Clonazepam or Alprazolam can help.
  • These drugs would reduce any anxiety and confusion. You should take these drugs with proper prescription only.
  • Avoid alcohol, excess tea or coffee for a few days.

Revert back to a general practitioner online for further follow up --> https://www.icliniq.com/ask-a-doctor-online/general-practitioner

Thank you doctor for your quick reply.

Yes, this was the first time I tried this extra dose for the persistent cough. I will never do this again. Why did this happen?


Hello again and welcome to icliniq.com.

  • These symptoms had occurred probably because of the anticholinergic side effects of Benadryl.
  • This may persist for a few days as confusion, dream like state etc.
  • With proper relaxation therapy and exercise you would improve.

For further follow up, consult a general practitioner online --> https://www.icliniq.com/ask-a-doctor-online/general-practitioner

Was this answer helpful?


Related Questions:
Why am I not happy no matter what the situation is?

I have been given some tranquilizers on top of my antidepressants and these have helped quite a bit but they make me sedated so not good when I am working ...   Read full

Mirap and Clonazepam prescribed for anxiety and depression, Is it fine to take?

Age 40Y, Male, minor knee pain sometime ,TAK Tak Sound when sit on kness, no injury , Family Heridatory , suggest precaution in diet or medicine for future   Read full

I am experiencing heavy shoulders and getting anxious that it could be a heart attack. Please help.

Age 40Y, Male, minor knee pain sometime ,TAK Tak Sound when sit on kness, no injury , Family Heridatory , suggest precaution in diet or medicine for future   Read full


This is a sponsored Ad. icliniq or icliniq doctors do not endorse the content in the Ad.

Also Read Answers From:

Comprehensive Medical Second Opinion.Submit your Case

Related Questions & Answers

To stop continuous panic attacks, which drug can be taken other than Clonazepam?

Query: Hi doctor, I have been on Klonopin that is Clonazepam prescribed before 14 years for panic attacks and anxiety. I am currently on the 2 mg dosage and taking it four times a day. This is monitored every few months by my family doctor. For the past one week, I have noticed that I have been experienc...  Read Full »

I had an allergic after eating cherries. What to do?

Query: Hi doctor, I had an allergic reaction after eating fresh cherries last night. My eyes began itching and then swelled up. It also started tearing. I woke up this morning with mild swelling on the inner parts of my eyes. I have attached the photo for your reference. Please help.  Read Full »

Can I take Hydroxyzine Hcl 25 mg while pregnant?

Query: Hi doctor, My wife is four months pregnant now. She has itchy palms. The doctor advised to take tablet Atarax 25 mg (Hydroxyzine hydrochloride). Is it safe to have this tablet during pregnancy? Kindly guide.  Read Full »

Also Read

Sinusitis - Causes, Symptoms and Treatment
Sinusitis is the infection of the air cavities within the nasal passages. Normally, the healthy sinuses are filled with ...  Read more»
Asthma and Its Rising Incidence
This article explains about asthma and its causes. It also focuses on the benefits of starting early treatment to lead a...  Read more»
Parkinson's Disease: Historical Aspects and Current Treatment Approaches
This article discusses the historical aspects of Parkinsonism and, the evidence based approaches currently available for...  Read more»

Ask your health query to a doctor online?

Ask a General Practitioner Now

* guaranteed answer within 4 hours.

Disclaimer: All health Q&As published on this website are not intended to be a substitute for professional medical diagnosis, advice or treatment by a trained physician. Seek the advice from your physician or other qualified health-care providers with questions you may have regarding your symptoms and medical condition for a complete medical diagnosis. Do not delay or disregard seeking professional medical advice because of something you have read on this website.