What is Trimethobenzamide
Trimethobenzamide is an oral, rectal, and parenteral antiemetic agent used to control nausea and vomiting.
Structurally, the drug is a substituted benzamide with actions similar to metoclopramide, but trimethobenzamide is considered less potent.
For example, trimethobenzamide is typically recommended only for control of nausea following chemotherapy of mild to moderate emetic potential.
Trimethobenzamide appears to have a favorable side effect profile when compared to the antiemetic phenothiazines. Per the manufacturer, the use of trimethobenzamide is likely best limited to treating prolonged vomiting of a known etiology.
Trimethobenzamide is not recommended for use in children due to the risk of extrapyramidal signs and symptoms and other serious CNS effects, and the risk of exacerbation of the underlying disease in pediatric patients with Reye’s syndrome or other hepatic impairment.
Trimethobenzamide was first marketed in 1959. The FDA has concluded that suppositories containing trimethobenzamide have not been proven to be effective in the treatment of nausea and vomiting.
Alternative treatment should be used. On April 6, 2007 the FDA called for the suspension of the marketing and distribution of trimethobenzamide rectal suppositories; drug companies wishing to have their products remain marketed so will have to submit a new drug application (NDA) and obtain FDA approval first.
Indications
- nausea/vomiting
Side Effects
- agranulocytosis
- angioedema
- blurred vision
- coma
- diarrhea
- dizziness
- drowsiness
- fever
- headache
- hypotension
- injection site reaction
- jaundice
- leukopenia
- muscle cramps
- pseudoparkinsonism
- rash
- seizures
- tremor
Monitoring Parameters
- laboratory monitoring not necessary
Contraindications
- agranulocytosis
- appendicitis
- bone marrow suppression
- breast-feeding
- children
- dehydration
- driving or operating machinery
- electrolyte imbalance
- encephalopathy
- ester local anesthetic hypersensitivity
- ethanol intoxication
- fever
- gastroenteritis
- geriatric
- hepatic disease
- hepatotoxicity
- infants
- intravenous administration
- jaundice
- neonates
- pregnancy
- premature neonates
- renal failure
- renal impairment
- Reye’s syndrome
- viral infection
Interactions
- Acetaminophen; Pentazocine
- Acetaminophen; Tramadol
- Alprazolam
- Amikacin
- Aminoglycosides
- Amitriptyline; Chlordiazepoxide
- Anticholinergics
- Anxiolytics; Sedatives; and Hypnotics
- Apomorphine
- Atropine
- Atropine; Benzoic Acid; Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate
- Atropine; Difenoxin
- Atropine; Diphenoxylate
- Atropine; Edrophonium
- Atropine; Hyoscyamine; Phenobarbital; Scopolamine
- Barbiturates
- Belladonna Alkaloids; Ergotamine; Phenobarbital
- Belladonna; Opium
- Benzodiazepines
- Benzoic Acid; Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate
- Benztropine
- Buprenorphine
- Buprenorphine; Naloxone
- Buspirone
- Butorphanol
- Chlordiazepoxide
- Chlordiazepoxide; Clidinium
- Chlorpromazine
- Clonazepam
- Clorazepate
- Codeine; Phenylephrine; Promethazine
- Codeine; Promethazine
- Dextromethorphan; Promethazine
- Diazepam
- Dicyclomine
- Dronabinol
- Droperidol
- Estazolam
- Ethanol
- Flavoxate
- Fluphenazine
- Flurazepam
- Gentamicin
- Glycopyrrolate
- Glycopyrrolate; Formoterol
- Homatropine; Hydrocodone
- Hyoscyamine
- Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate; Sodium Biphosphate
- Indacaterol; Glycopyrrolate
- Ipecac
- Kanamycin
- Lorazepam
- Mepenzolate
- Meperidine; Promethazine
- Mesoridazine
- Methenamine; Sodium Acid Phosphate; Methylene Blue; Hyoscyamine
- Methscopolamine
- Midazolam
- Nabilone
- Nalbuphine
- Opiate Agonists
- Oxazepam
- Oxybutynin
- Paromomycin
- Pentazocine
- Pentazocine; Naloxone
- Perphenazine
- Perphenazine; Amitriptyline
- Phenothiazines
- Phenylephrine; Promethazine
- Plazomicin
- Prochlorperazine
- Promethazine
- Propantheline
- Quazepam
- Scopolamine
- Sedating H1-blockers
- Sodium Oxybate
- Streptomycin
- Temazepam
- Teniposide
- Thiethylperazine
- Thioridazine
- Tobramycin
- Tramadol
- Triazolam
- Trifluoperazine
- Trihexyphenidyl
- Trospium