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6 Interactions found for:

Benadryl and tizanidine
Interactions Summary
  • 2 Major
  • 2 Moderate
  • 2 Minor
  • Benadryl
  • tizanidine

Drug Interactions

Moderate
Benadryl + Tizanidine

The following applies to the ingredients: Diphenhydramine (found in Benadryl) and Tizanidine

Using tiZANidine together with diphenhydrAMINE may increase side effects such as dizziness, drowsiness, confusion, and difficulty concentrating. Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination. You should avoid or limit the use of alcohol during treatment. In addition, these medications may also have additive effects in lowering your blood pressure. You may experience headache, dizziness, lightheadedness, fainting, and/or changes in pulse or heart rate. These side effects are most likely to be seen at the beginning of treatment, following a dose increase, or when treatment is restarted after an interruption. Let your doctor know if you develop these symptoms and they do not go away after a few days or they become troublesome. Avoid driving or operating hazardous machinery until you know how the medications affect you, and use caution when getting up from a sitting or lying position. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Drug and Food Interactions

Moderate
Benadryl + Food

The following applies to the ingredients: Diphenhydramine (found in Benadryl)

Ask your doctor before using diphenhydrAMINE together with ethanol. Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while you are taking diphenhydrAMINE. You should be warned not to exceed recommended dosages and to avoid activities requiring mental alertness. If your doctor prescribes these medications together, you may need a dose adjustment to safely take this combination. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Drug and Pregnancy Interactions

The following applies to the ingredients: Diphenhydramine (found in Benadryl)

Professional Content

Use is recommended only if clearly needed and the benefit outweighs the risk.

AU TGA pregnancy category: A
US FDA pregnancy category: B

Comment:
-Exposure during the third trimester may result in adverse reactions in premature infants and neonates.

Animal models have failed to reveal evidence of impaired fertility or fetal harm at doses up to 5 times the human dose. There are no controlled data in human pregnancy.

AU TGA pregnancy category A: Drugs which have been taken by a large number of pregnant women and women of childbearing age without any proven increase in the frequency of malformations or other direct or indirect harmful effects on the fetus having been observed.

US FDA pregnancy category B: Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.

References

  1. "Product Information. Benadryl (diphenhydramine)." Parke-Davis PROD (2002):
  2. "Product Information. Benadryl Children's Allergy Fastmelt (diphenhydrAMINE)." Pfizer U.S. Pharmaceuticals Group (2022):
  3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  4. Cerner Multum, Inc. "Australian Product Information." O 0
  5. "Product Information. DiphenhydrAMINE Hydrochloride (diphenhydramine)." West-Ward Pharmaceuticals Corporation (previously Roxane Laboratories Inc) (2019):

The following applies to the ingredients: Tizanidine

Professional Content

Benefit should outweigh risk

US FDA pregnancy category: C

Teratogenicity was not shown in animal studies in rats and rabbits. At doses up to 8 times the maximum recommended human dose, increased gestation duration was observed in rats. Pre and prenatal and postnatal pup loss and developmental retardation occurred in rats and rabbits and post-implantation loss was increased in rabbits at doses of 1 mg/kg or more. There are no controlled studies in pregnant women.

US FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

References

  1. "Product Information. Zanaflex (tizanidine)." Acorda Therapeutics PROD (2001):

Drug and Breastfeeding Interactions

The following applies to the ingredients: Diphenhydramine (found in Benadryl)

Professional Content

Use is not recommended.
-According to some authorities: Use is contraindicated.

Excreted into human milk: Yes

Comments:
-The effects in the nursing infant are unknown.
-This drug may affect milk production, especially at high doses given early in the postpartum period and/or when used concomitantly with a sympathomimetic drug.

References

  1. "Product Information. Benadryl (diphenhydramine)." Parke-Davis PROD (2002):
  2. "Product Information. Benadryl Children's Allergy Fastmelt (diphenhydrAMINE)." Pfizer U.S. Pharmaceuticals Group (2022):
  3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  4. Cerner Multum, Inc. "Australian Product Information." O 0
  5. United States National Library of Medicine "Toxnet. Toxicology Data Network. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT" (2013):

The following applies to the ingredients: Tizanidine

Professional Content

Safety has not been established

Excreted into human milk: Unknown
Excreted into animal milk: Yes

Comments: If used, monitor infant for toxicity such as sedation, hypotension, and hallucinations.

As a lipid soluble drug, it might be expected to pass into breast milk.

References

  1. "Product Information. Zanaflex (tizanidine)." Acorda Therapeutics PROD (2001):
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

Therapeutic Duplication Warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.

Switch to: Professional Interactions

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

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