Can You Take Tylenol PM with Benadryl?
No, you should not take Tylenol PM with Benadryl. Both contain diphenhydramine, an antihistamine that causes drowsiness. Taking them together risks serious overdose effects like extreme sedation, confusion, respiratory depression, or coma.[1][2]
What's in Tylenol PM?
Tylenol PM combines 500 mg acetaminophen (pain reliever) per caplet with 25 mg diphenhydramine HCl (sleep aid).[3] Benadryl typically has 25 mg diphenhydramine per dose.[4] The overlap is the diphenhydramine—doubling up exceeds safe limits (usually 25-50 mg every 4-6 hours for adults, max 300 mg/day).[1]
What Happens If You Mix Them?
Excess diphenhydramine amplifies side effects:
- Severe drowsiness or inability to wake.
- Dry mouth, blurred vision, constipation.
- Heart palpitations, seizures, or hallucinations in high doses.
- Risk rises with alcohol, other sedatives, or conditions like glaucoma, asthma, or prostate issues.[2][5]
Acetaminophen adds liver strain risk if overused, though not directly from this combo.[3]
Are There Exceptions or Safer Alternatives?
Avoid entirely unless a doctor approves a lower dose for specific needs. Children, elderly, or those with liver/kidney problems face higher risks.[1]
- For pain + sleep: Plain Tylenol (acetaminophen only) with melatonin.
- For allergies + sleep: Plain Benadryl alone, or non-drowsy options like loratadine (Claritin) + separate acetaminophen.
- Prescription alternatives: Talk to a pharmacist for doxylamine (Unisom) if needed, but check interactions.[5]
When to See a Doctor?
If you've already taken both, monitor for symptoms and call poison control (1-800-222-1222 in US) or seek emergency care for trouble breathing or unresponsiveness.[2] Always check labels and use tools like Drugs.com interaction checker before mixing.[1]
[1]: Drugs.com - Tylenol PM and Benadryl Interaction
[2]: WebMD - Diphenhydramine Overdose Risks
[3]: Tylenol.com - Tylenol PM Ingredients
[4]: Benadryl.com - Dosage Info
[5]: FDA - OTC Sleep Aid Warnings