What is diphenhydramine used for?

Indications and Usage, quoted from the label by Micro Labs Limited (ANDA205723). Cross-references to other label sections are left out.

Diphenhydramine hydrochloride in the injectable form is effective in adults and pediatric patients, other than premature infants and neonates, for the following conditions when diphenhydramine hydrochloride in the oral form is impractical.

Antihistaminic

For amelioration of allergic reactions to blood or plasma, in anaphylaxis as an adjunct to epinephrine and other standard measures after the acute symptoms have been controlled, and for other uncomplicated allergic conditions of the immediate type when oral therapy is impossible or contraindicated.

Motion sickness

For active treatment of motion sickness.

Antiparkinsonism

For use in parkinsonism, when oral therapy is impossible or contraindicated, as follows: parkinsonism in the elderly who are unable to tolerate more potent agents; mild cases of parkinsonism in other age groups, and in other cases of parkinsonism in combination with centrally acting anticholinergic agents.

Source: DailyMed label, set id a1110433-498a-48cb-ac79-5732fd4f8fba, version 11, effective March 5, 2026. NDC 42571-169, one of 16 listings for this product.

Indications and Usage, quoted from the label by Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc. (ANDA205337). Cross-references to other label sections are left out.

Diphenhydramine hydrochloride injection, USP is effective in adults and pediatric patients, other than premature infants and neonates, for the following conditions when the oral form is impractical.

Antihistaminic

For amelioration of allergic reactions to blood or plasma, in anaphylaxis as an adjunct to epinephrine and other standard measures after the acute symptoms have been controlled and for other uncomplicated allergic conditions of the immediate type when oral therapy is impossible or contraindicated.

Motion Sickness

For active treatment of motion sickness.

Antiparkinsonism

For use in parkinsonism, when oral therapy is impossible or contraindicated, as follows: parkinsonism in the elderly who are unable to tolerate more potent agents, mild cases of parkinsonism in other age groups and in other cases of parkinsonism in combination with centrally acting anticholinergic agents.

Source: DailyMed label, set id 6178d3a1-0741-49a4-be81-c4f7d29f8b2a, version 5, effective November 18, 2025. NDC 23155-263, one of 15 listings for this product.

Indications and Usage, quoted from the label by Redmont Pharmaceuticals, LLC (ANDA087513). Cross-references to other label sections are left out.

Diphenhydramine hydrochloride in the oral form is effective for the following indications:

Antihistaminic

For allergic conjunctivitis due to foods; mild, uncomplicated allergic skin manifestations of urticaria and angioedema; amelioration of allergic reactions to blood or plasma; dermatographism; as therapy for anaphylactic reactions adjunctive to epinephrine and other standard measures after the acute manifestations have been controlled.

Motion Sickness

For active and prophylactic treatment of motion sickness.

Antiparkinsonism

For parkinsonism (including drug-induced) in the elderly unable to tolerate more potent agents; mild cases of parkinsonism (including drug-induced) in other age groups; in other cases of parkinsonism (including drug-induced) in combination with centrally acting anticholinergic agents.

Nighttime Sleep-aid.

Source: DailyMed label, set id d8944f3c-acef-4ebe-9633-7d641ae95edf, version 2, effective August 3, 2026. NDC 71741-511, one of 6 listings for this product.