Included In This Lesson
Study Tools
Outline
Generic Name
Diphenhydramine
Trade Name
Benadryl
Indication
Allergy, anaphylaxis, sedation, motion sickness, antitussive
Action
Antagonizes effects of histamine, CNS depression
Therapeutic Class
Allergy, cold and cough remedy, antihistamine, antitussive
Pharmacologic Class
Antihistamine
Nursing Considerations
• May cause drowsiness, anorexia, dry mouth, nausea, chest tightness, thick
secretions, hypotension, blurred vision, headache
• Anticholinergic effects (dry mouth, blurred vision, constipation, sedation)
• Assess purpose of medication prior to giving it
• Assess allergies, sleep patterns, cough and lung sounds
• Patient should avoid other over-the-counter cough and cold remedies
Transcript
Let’s talk about, diphenhydramine also known as Benadryl. This is an oral medication, but it also comes in other forms like topical and IV, as you can see here. So remember when we talk about the therapeutic class, we are talking about what the drug does in the body while the pharmacologic class is the drug’s chemical effect. So the therapeutic class of diphenhydramine is an allergy, cold, and cough remedy. It’s an antihistamine and an antitussive, which is a cough suppressant. The pharmacologic class of diphenhydramine is an antihistamine. So diphenhydramine works by antagonizing the effects of histamine causing central nervous system depression. Diphenhydramine is indicated for allergies, anaphylaxis, sedation, motion sickness, and as a cough suppressant or antitussive. So remember, diphenhydramine ends up causing central nervous system depression, so with that can come some side effects, including drowsiness, dry mouth, anorexia, and headache.
So let’s take a look at a few nursing considerations for diphenhydramine. Be sure to assess the purpose of giving this medication prior to administering. Also assess your patient’s allergies, sleep patterns, cough, and lung sounds during therapy. Remember that there are some anticholinergic effects that occur with diphenhydramine, including constipation, dry mouth, blurred, vision, and sedation. Some additional issues can occur, including chest tightness, thick secretions, and hypotension. An extra little bit of information: be especially careful if your patient has dementia and is on any acetylcholinesterase inhibitors; diphenhydramine in these medications directly inhibit each other, meaning this could lead to worsening dementia and worsening of the issue the patient was on was taking diphenhydramine for in the first place. And also guys teach the patient to avoid over-the-counter cough and cold remedies. That’s it for diphenhydramine or Benadryl. Now go out and be your best self today and as always happy nursing.
Tarang Patel, DNP-NA, RN, CCRN, RPh 
Nichole Weaver, MSN/Ed, RN, CCRN 
Miriam Wahrman, MSN/Ed, RNC-MNN 
Kara Tarr, BSN, RN 
Nacole Riccaboni, MSN, AGACNP-BC, FNP-BC, CCRN, CMC 