7 Interactions found for:
- 2 Major
- 3 Moderate
- 2 Minor
Drug Interactions
Moderate
Benadryl
+ Zyrtec
The following applies to the ingredients: Diphenhydramine (found in Benadryl) and Cetirizine (found in Zyrtec)
MONITOR: Concurrent use of cetirizine or levocetirizine with alcohol or other agents that exhibit central nervous system (CNS) depressant effects may result in additive impairment of mental alertness and performance. Several studies have shown no effect of racemic cetirizine on cognitive function, motor performance, or sleep latency as indicated by objective measurements. However, there have been reports of somnolence, fatigue, and asthenia in some patients treated with cetirizine or levocetirizine in clinical trials.
MANAGEMENT: Concomitant use of cetirizine or levocetirizine with alcohol or other CNS depressants should generally be avoided if possible. In the event that they are used together, patients should be counseled against driving, operating machinery, or engaging in potentially hazardous activities requiring mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.
References
- "Product Information. Zyrtec (cetirizine)." Pfizer U.S. Pharmaceuticals PROD (2001):
- "Product Information. Xyzal (levocetirizine)." UCB Pharma Inc (2007):
Drug and Food Interactions
Moderate
Zyrtec
+ Food
The following applies to the ingredients: Cetirizine (found in Zyrtec)
GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of CNS-active agents. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills.
MANAGEMENT: Patients receiving CNS-active agents should be warned of this interaction and advised to avoid or limit consumption of alcohol. Ambulatory patients should be counseled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.
References
- Warrington SJ, Ankier SI, Turner P "Evaluation of possible interactions between ethanol and trazodone or amitriptyline." Neuropsychobiology 15 (1986): 31-7
- Gilman AG, eds., Nies AS, Rall TW, Taylor P "Goodman and Gilman's the Pharmacological Basis of Therapeutics." New York, NY: Pergamon Press Inc. (1990):
- "Product Information. Fycompa (perampanel)." Eisai Inc (2012):
- "Product Information. Rexulti (brexpiprazole)." Otsuka American Pharmaceuticals Inc (2015):
Moderate
Benadryl
+ Food
The following applies to the ingredients: Diphenhydramine (found in Benadryl)
GENERALLY AVOID: Use of anticholinergic agents with alcohol may result in sufficient impairment of attention so as to render driving and operating machinery more hazardous. In addition, the potential for abuse may be increased with the combination. The mechanism of interaction is not established but may involve additive depressant effects on the central nervous system. No effect of oral propantheline or atropine on blood alcohol levels was observed in healthy volunteers when administered before ingestion of a standard ethanol load. However, one study found impairment of attention in subjects given atropine 0.5 mg or glycopyrrolate 1 mg in combination with alcohol.
MANAGEMENT: Alcohol should generally be avoided during therapy with anticholinergic agents. Patients should be counseled to avoid activities requiring mental alertness until they know how these agents affect them.
References
- Linnoila M "Drug effects on psychomotor skills related to driving: interaction of atropine, glycopyrrhonium and alcohol." Eur J Clin Pharmacol 6 (1973): 107-12
Drug and Pregnancy Interactions
Minor
Benadryl
+ Pregnancy
The following applies to the ingredients: Diphenhydramine (found in Benadryl)
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
- "Product Information. Benadryl (diphenhydramine)." Parke-Davis PROD (2002):
- "Product Information. Benadryl Children's Allergy Fastmelt (diphenhydrAMINE)." Pfizer U.S. Pharmaceuticals Group (2022):
- Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
- Cerner Multum, Inc. "Australian Product Information." O 0
- "Product Information. DiphenhydrAMINE Hydrochloride (diphenhydramine)." West-Ward Pharmaceuticals Corporation (previously Roxane Laboratories Inc) (2019):
Minor
Zyrtec
+ Pregnancy
The following applies to the ingredients: Cetirizine (found in Zyrtec)
This drug should not be used during pregnancy unless the benefit outweighs the risk to the fetus.
AU TGA pregnancy category: B2
US FDA pregnancy category: Not formally assigned to a pregnancy category.
Animal models have failed to reveal evidence of teratogenicity and harmful effects on pregnancy, embryofetal development, parturition, and/or postnatal development. There are no controlled data in human pregnancy.
AU TGA pregnancy category B2: Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals are inadequate or may be lacking, but available data show no evidence of an increased occurrence of fetal damage.
US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.
References
- "Product Information. Zyrtec (cetirizine)." Pfizer U.S. Pharmaceuticals PROD (2001):
- Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
- Cerner Multum, Inc. "Australian Product Information." O 0
Drug and Breastfeeding Interactions
Major
Benadryl
+ Breastfeeding
The following applies to the ingredients: Diphenhydramine (found in Benadryl)
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
- "Product Information. Benadryl (diphenhydramine)." Parke-Davis PROD (2002):
- "Product Information. Benadryl Children's Allergy Fastmelt (diphenhydrAMINE)." Pfizer U.S. Pharmaceuticals Group (2022):
- Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
- Cerner Multum, Inc. "Australian Product Information." O 0
- United States National Library of Medicine "Toxnet. Toxicology Data Network. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT" (2013):
Major
Zyrtec
+ Breastfeeding
The following applies to the ingredients: Cetirizine (found in Zyrtec)
Use with caution.
-Some experts recommend: Use is not recommended.
Excreted into human milk: Yes
Drug concentrations in breastmilk were approximately 25% to 90% of drug concentrations in plasma.
References
- "Product Information. Zyrtec (cetirizine)." Pfizer U.S. Pharmaceuticals PROD (2001):
- Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
- Cerner Multum, Inc. "Australian Product Information." O 0
- United States National Library of Medicine "Toxnet. Toxicology Data Network. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT" (2013):
- Department of Adolescent and Child Health and Development. UNICEF. World Health Organization "Breastfeeding and maternal medication: recommendations for drugs in the eleventh Who model list of essential drugs. http://whqlibdoc.who.int/hq/2002/55732.pdf?ua=1" (2014):
Therapeutic Duplication Warnings
Warning
Antihistamines
The following applies to: Benadryl (diphenhydramine), Zyrtec (cetirizine)
The recommended maximum number of medicines in the 'antihistamines' category to be taken concurrently is usually one. Your list includes two medicines.
Therapeutic duplication is the use of more than one medicine from the same drug category or therapeutic class to treat the same condition. This can be intentional in cases where drugs with similar actions are used together for demonstrated therapeutic benefit. It can also be unintentional in cases where a patient has been treated by more than one doctor, or had prescriptions filled at more than one pharmacy, and can have potentially adverse consequences.
Switch to: Consumer Interactions
Drug Interaction Classification | |
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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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