What it means
An older antihistaminean-tee-HIS-tuh-meenA drug that blocks the effects of histamine, used mostly for allergy symptoms.anti- againsthistamine Full entry that blocks histamine and also has strong anticholinergican-tee-koh-lin-ER-jikA drug or effect that blocks acetylcholine, a nerve messenger, in parts of the nervous system.anti- againstcholinergic acting like acetylcholineFull entry effects. It treats allergic reactions, hives and itching, is added to epinephrine in anaphylaxis, prevents motion sickness, is used as a sleep aid, and reverses acute dystonia caused by antipsychotics. It makes most people drowsy and can cause dry mouth, blurred vision, constipation, trouble passing urine and confusion, especially in older adults.
For the nurse
Teach the client to avoid driving and alcohol, and to check labels, since it is in many cold and sleep products. Watch older adults for confusion, falls and urinary retention.
At a glance
| Drug class | antihistamine (first-generation H1 blocker) |
|---|---|
| Brand names | Benadryl |
| Spanish | difenhidramina |
| Also written | Benadryl |
Related terms
anaphylaxis
A sudden, severe allergic reaction that affects the whole body.
antihistamine
A drug that blocks the effects of histamine, used mostly for allergy symptoms.
anticholinergic
A drug or effect that blocks acetylcholine, a nerve messenger, in parts of the nervous system.
dystonia
Muscle contractions that a person cannot control, which twist part of the body into an unusual position.