Get Expert Advice for controlling your Severe Allergies

Benadryl (diphenhydramine) Disease Interactions

There are 4 disease interactions with Benadryl (diphenhydramine):

Antihistamines (Includes Benadryl) ↔ Anticholinergic Effects

Severe Potential Hazard, High plausibility

Applies to: Gastrointestinal Obstruction, Urinary Retention, Glaucoma/Intraocular Hypertension

Antihistamines often have anticholinergic activity, to which elderly patients are particularly sensitive. Therapy with antihistamines should be administered cautiously, if at all, in patients with preexisting conditions that are likely to be exacerbated by anticholinergic activity, such as urinary retention or obstruction; angle-closure glaucoma, untreated intraocular hypertension, or uncontrolled primary open-angle glaucoma; and gastrointestinal obstructive disorders. Conventional, first-generation antihistamines such as the ethanolamines (bromodiphenhydramine, carbinoxamine, clemastine, dimenhydrinate, diphenhydramine, doxylamine, phenyltoloxamine) tend to exhibit substantial anticholinergic effects. In contrast, the newer, relatively nonsedating antihistamines (e.g., cetirizine, fexofenadine, loratadine) reportedly have low to minimal anticholinergic activity at normally recommended dosages and may be appropriate alternatives.

References

  1. "Product Information. Optimine (azatadine)." Schering Laboratories, Kenilworth, NJ.
  2. "Product Information. Periactin (cyproheptadine)." Merck & Co, Inc, West Point, PA.
  3. "Product Information. Tavist (clemastine)." Sandoz Pharmaceuticals Corporation, East Hanover, NJ.
View all 20 references

Antihistamines (Includes Benadryl) ↔ Asthma/Copd

Moderate Potential Hazard, Moderate plausibility

Applies to: Asthma, Chronic Obstructive Pulmonary Disease

It has been suggested that the anticholinergic effect of antihistamines may reduce the volume and cause thickening of bronchial secretions, resulting in obstruction of respiratory tract. Some manufacturers and clinicians recommend that therapy with antihistamines be administered cautiously in patients with asthma or chronic obstructive pulmonary disease.

References

  1. "Product Information. Temaril (trimeprazine)" Allergan Inc, Irvine, CA.
  2. "Product Information. Tavist (clemastine)." Sandoz Pharmaceuticals Corporation, East Hanover, NJ.
  3. "Product Information. Periactin (cyproheptadine)." Merck & Co, Inc, West Point, PA.
View all 17 references

Antihistamines (Includes Benadryl) ↔ Cardiovascular

Moderate Potential Hazard, Moderate plausibility

Applies to: Cardiovascular Disease, Hyperthyroidism, Hypotension

Antihistamines may infrequently cause cardiovascular adverse effects related to their anticholinergic and local anesthetic (quinidine-like) activities. Tachycardia, palpitation, ECG changes, arrhythmias, hypotension, and hypertension have been reported. Although these effects are uncommon and usually limited to overdosage situations, the manufacturers and some clinicians recommend that therapy with antihistamines be administered cautiously in patients with cardiovascular disease, hypertension, and/or hyperthyroidism.

References

  1. "Product Information. Dimetane (brompheniramine)." Wyeth-Ayerst Laboratories, Philadelphia, PA.
  2. "Product Information. Chlortrimeton (chlorpheniramine)." Schering-Plough, Liberty Corner, NJ.
  3. "Product Information. Optimine (azatadine)." Schering Laboratories, Kenilworth, NJ.
View all 15 references

Antihistamines (Includes Benadryl) ↔ Renal/Liver Disease

Moderate Potential Hazard, High plausibility

Applies to: Liver Disease, Renal Dysfunction

Limited pharmacokinetic data are available for the older, first-generation antihistamines. Many appear to be primarily metabolized by the liver, and both parent drugs and metabolites are excreted in the urine. Patients with renal and/or liver disease may be at greater risk for adverse effects from antihistamines due to drug and metabolite accumulation. Therapy with antihistamines should be administered cautiously in such patients. Lower initial dosages may be appropriate.

References

  1. Paton DM, Webster DR "Clinical pharmacokinetics of H1-receptor antagonists (the antihistamines)." Clin Pharmacokinet 10 (1985): 477-97
  2. Rumore MM "Clinical pharmacokinetics of chlorpheniramine." Drug Intell Clin Pharm 18 (1984): 701-7
  3. Simons FE, Frith EM, Simons KJ "The pharmacokinetics and antihistaminic effects of brompheniramine." J Allergy Clin Immunol 70 (1982): 458-64
View all 15 references

You should also know about...

Benadryl (diphenhydramine) drug Interactions

There are 734 drug interactions with Benadryl (diphenhydramine)

Benadryl (diphenhydramine) alcohol/food Interactions

There is 1 alcohol/food interaction with Benadryl (diphenhydramine)

Drug Interaction Classification

The classifications below are a general guideline only. It is difficult to determine the relevance of a particular drug interaction to any individual given the large number of variables.

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.

Do not stop taking any medications without consulting your healthcare provider.

Disclaimer: Every effort has been made to ensure that the information provided by Multum is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. Multum's information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill, knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective, or appropriate for any given patient. Multum Information Services, Inc. does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. Copyright 2000-2014 Multum Information Services, Inc. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse, or pharmacist.

Hide
(web4)