Dimenhydrinate Injection USP

Rx only

Dimenhydrinate, an anti-nauseant/antiemetic, is the 8-chlorotheophylline salt of diphenhydramine. It contains not less than 53% and not more than 55.5% of diphenhydramine, and not less than 44% and not more than 47% of 8-chlorotheophylline, calculated on the dried basis. Chemically, it is 8-chlorotheophylline compound with 2(diphenylmethoxy)-N,N-dimethylethylamine (1:1), and the structural formula is:

C₁₇H₂₁NO•C₇H₇ClN₄O₂                               M.W. 469.96

Dimenhydrinate Injection, USP contains a sterile solution of Dimenhydrinate 50 mg/mL; Propylene Glycol 50%; Benzyl Alcohol 5% as preservative; and Water for Injection q.s. Sodium Hydroxide and/or Hydrochloric Acid may have been used to adjust pH.

While the precise mode of action of dimenhydrinate is not known, it has a depressant action on hyperstimulated labyrinthine function.

Dimenhydrinate Injection, USP is indicated for the prevention and treatment of nausea, vomiting, or vertigo of motion sickness.

Neonates and patients with a history of hypersensitivity to dimenhydrinate or its components (diphenhydramine or 8-chlorotheophylline) should not be treated with dimenhydrinate.

Note: This product contains Benzyl Alcohol. Benzyl Alcohol has been associated with a fatal “Gasping Syndrome” in premature infants and infants of low birth weight.

Caution should be used when dimenhydrinate is given in conjunction with certain antibiotics that may cause ototoxicity, since dimenhydrinate is capable of masking ototoxic symptoms, and an irreversible state may be reached.

This drug may impair the mental and/or physical abilities required for the performance of potentially hazardous tasks, such as driving a vehicle or operating machinery. The concomitant use of alcohol or other central nervous system depressants may have an additive effect. Therefore, patients should be warned accordingly.

Dimenhydrinate should be used with caution in patients having conditions which might be aggravated by anticholinergic therapy (i.e., prostatic hypertrophy, stenosing peptic ulcer, pyloroduodenal obstruction, bladder neck obstruction, narrow-angle glaucoma, bronchial asthma, or cardiac arrhythmias).

The preparation should not be injected intra-arterially.

The most frequent adverse reaction to dimenhydrinate is drowsiness. Dizziness may also occur. Symptoms of dry mouth, nose and throat, blurred vision, difficult or painful urination, headache, anorexia, nervousness, restlessness or insomnia (especially in pediatric patients), skin rash, thickening of bronchial secretions, tachycardia, epigastric distress, lassitude, excitation, and nausea have been reported.

Drowsiness is the usual clinical side effect. Convulsions, coma, and respiratory depression may occur with massive overdosage. No specific antidote is known. If respiratory depression occurs, mechanically assisted respiration should be initiated and oxygen should be administered. Convulsions should be treated with appropriate doses of diazepam. Phenobarbital (5 to 6 mg/kg) may be given to control convulsions in pediatric patients.

The oral LD₅₀ in mice and rats is 203 mg/kg and 1320 mg/kg, respectively. The intraperitoneal LD₅₀ in mice is 149 mg/kg.

Dimenhydrinate in the injectable form is indicated when the oral form is impractical.

DimenhyDRINATE Injection, USP, 50 mg/mL is available in multiple dose amber vials, as follows:

Protect from light.

Store at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature].

The container closure is not made with natural rubber latex.

45981C

Revised: August 2024

PACKAGE LABEL - PRINCIPAL DISPLAY - Dimenhydrinate 1 mL Vial Label

NDC 63323-366-00          361601

DimenhyDRINATE
INJECTION, USP

50 mg per mL

For IM Use
For IV Use: See package insert.

Rx only

1 mL Multiple Dose Vial

PACKAGE LABEL - PRINCIPAL DISPLAY - Dimenhydrinate 1 mL Vial Tray Label

NDC 63323-366-01           361601

DimenhyDRINATE
INJECTION, USP

50 mg per mL

For IM Use

*For IV Use

Rx only

25 x 1 mL
Multiple Dose Vials