Can You Take Benadryl With Soma?
Our pharmacist discusses the drug interaction between Benadryl (diphenhydramine) and Soma (carisoprodol).
I take Soma every once in a while, for back pain from a car accident years ago. I want to take some Benadryl to help me sleep. Is that okay?
Oct 28, 2022- Benadryl and Soma are both central nervous system depressants and taking them together can increase drowsiness, dizziness, and sedation. Your doctor may recommend using both drugs together if clinically appropriate, but you should avoid activities requiring mental alertness like driving. Separating the doses by 4 to 8 hours can help reduce the additive effects of these medications.
Benadryl With Soma - Interaction Details
There is a drug interaction between Benadryl (diphenhydramine) and Soma (carisoprodol). Both drugs are CNS (central nervous system) depressants and combining them can cause additive effects, such as pronounced sedation, dizziness, and drowsiness.
There is a blanket interaction warning between any two drugs that are classified as CNS depressants. The prescribing information for Soma states this specifically:
Patients should be advised to avoid alcoholic beverages while taking SOMA and to check with their doctor before taking other CNS depressants such as benzodiazepines, opioids, tricyclic antidepressants, sedating antihistamines, or other sedatives.
Benadryl is a sedating antihistamine, and thus, included in this warning.
How To Manage This Interaction
As both these drugs can cause similar side effects (e.g., sedation, drowsiness), their combined use should generally be avoided, especially if you are doing activities that require you to be mentally alert, like driving.
Having said this, it's not uncommon that your doctor may recommend that you use two or more drugs that have the potential to depress CNS function if clinically appropriate. It is just important to recognize that the risk of side effects may increase when these types of drugs are combined. Now, since you mentioned taking Benadryl only at night to help you sleep, this interaction may not affect you as much, but you still want to be cautious, and it would be prudent to start at a low dose of either drug and separate their dosing.
In fact, if you want to avoid their additive effects as much as you can, it would be prudent to separate their dosing.
Soma lasts around 4 to 8 hours per dose, while Benadryl lasts about 4 to 6 hours per dose so you should separate them by an appropriate amount of time (4 to 8 hours).
Drug Details
If you are looking for more information on either Benadryl or Soma, you can check out our drug detail pages:
You can also reach out to us directly and a pharmacist would be more than happy to answer your question!
Final Words
Thanks for contacting us and I hope this helped!
References & sources
Glossary — Terms in This Answer
- CNS depressants
- Drugs that slow down brain and nervous system activity, reducing alertness and causing drowsiness.
- Additive effects
- When two drugs combine to produce a stronger effect than either drug would produce alone.
- Sedation
- A state of calm or reduced consciousness, often induced by medication.
- Antihistamine
- A drug that blocks the effects of histamine, a natural substance in the body that causes allergic reactions and inflammation.
- Benzodiazepines
- A class of drugs that calm the nervous system and are often used to treat anxiety or sleep problems.
- Opioids
- Strong pain-relieving drugs derived from or similar to opium that work on the nervous system.
- Tricyclic antidepressants
- An older type of antidepressant medication used to treat depression and certain pain conditions.
- Prescribing information
- Official documentation from a drug manufacturer that describes the medication's uses, dosages, side effects, and warnings.
Dr. Brian Staiger, PharmD
Doctor of Pharmacy, board certified clinical pharmacist (BCPS), American Herbalist Guild, Medication Therapy Management certified
Brian Staiger, PharmD, BCPS, is a licensed pharmacist with more than 13 years of experience across retail pharmacy, clinical pharmacy, medication safety, pharmacy program development, and healthcare administration. He is the founder of HelloPharmacist.com, where he helps patients...
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