-
-
Class
antihistamine; anticholinergic
-
Mechanism of action
Blocks cellular histamine receptors; decreases vasodilation; decreases motion sickness. Reverses extrapyramidal reactions
-
Indications
Symptomatic relief of allergies, allergic reactions, anaphylaxis, acute dystonic reactions (phenothiazines). Blood administration reactions, used for motion sickness, hay fever.
-
Contraindications
Asthma, glaucoma, pregnancy, hypertension, narrow angle glaucoma, infants pts. taking monoamine oxidase inhibitors (MAOIs).
-
Adverse Reactions
Sedation, hypotension seizures, visual disturbances, vomiting, urinary retention, palpitations, arrhythmias, dry mouth and throat, and dparadoxical CNS excitation in children.
-
Drug Interactions
Potentiates effects of alcohol and other anticholinergics, may inhibit corticosteroid activity; MAOIs prolong anticholinergic effects of diphenhydramine.
-
How Supplied
- Tablets: 25, 50mg
- Capsules: 25, 50 mg
- Prefilled syringes: 50 or 100 mg vials (IV or IM)
- Elixer: 12.5 mg/5mL
-
Dosage and administration
- Adult: 25-50 mg IM or IV or PO.
- Pediatric: 1-2 mg/kg IV, IO slowly or IM
- if given PO: 5 mg/kg/24hrs.
-
Duration of action
- Onset: 15-30 minutes
- Peak effect: 1 hour
- Duration: 3-12 hours
-
Special Considerations
Not used in infants or in pregnancy: category B. If used in anaphylaxis, will be in conjunction with epinephrine, corticosteroids.
|
|
