Trimethobenzamide

Trimethobenzamide is a novel antiemetic which prevents nausea and vomiting in humans. Its actions are unclear but most likely involves the chemoreceptor trigger zone (CTZ). In dogs pretreated with Trimethobenzamide HCl, the emetic response to apomorphine is inhibited, while little or no protection is afforded against emesis induced by intragastric copper sulfate.

Trimethobenzamide® (Trimethobenzamide injectable) is indicated for the treatment of postoperative nausea and vomiting and for nausea associated with gastroenteritis.

Trimethobenzamide affects the areas of the brain that stimulate nausea and vomiting.

Trimethobenzamide is used to treat nausea and vomiting related to surgery or caused by stomach flu.

Trimethobenzamide may also be used for purposes not listed in this medication guide.

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Capsule,

Oral, as hydrochloride:

Trimethobenzamide: 300 mg

Generic: 300 mg

Solution,

Intramuscular, as hydrochloride:

Trimethobenzamide: 100 mg/mL (2 mL)

Trimethobenzamide: 100 mg/mL (20 mL) [contains phenol]

Dosing: Adult

Nausea/vomiting: Note: Use the lowest effective dosage based on response and tolerability.

IM: 200 mg 3 or 4 times daily

Oral: 300 mg 3 or 4 times daily

Dosing: Geriatric

Refer to adult dosing; reduce the dose or increase the dosing interval and adjust as needed based on patient response.

Dosing: Pediatric

Note: Use in pediatric patients is strongly discouraged due to risk of EPS, serious CNS effects, and other adverse reactions. Expert recommendations for nausea and vomiting management do not suggest Trimethobenzamide as a therapeutic option; use has been replaced by newer agents with an improved safety profile (MMWR 2003; SAA [Gan 2014]). Although rectal dosing may still be referred to in pediatric textbooks, rectal formulations of Trimethobenzamide are no longer available.

Parenteral formulations are contraindicated in pediatric patients.

Nausea and vomiting, opioid induced: Limited data available (Kliegman 2016): Children and Adolescents:

<15 kg:

Oral: 100 mg every 6 hours as needed

≥15 kg:

Oral: 200 mg every 6 hours as needed

See also:
What is the most important information I should know about Trimethobenzamide?

Seek emergency medical attention if you think you have used too much of this medicine. Symptoms of a Trimethobenzamide overdose may include drowsiness, uncontrollable movements, muscle spasms, blurred vision, seizures or convulsions, difficulty breathing, and death.

Trimethobenzamide may increase the side effects of other drugs that make you sleepy (such as alcohol, cold medicine, pain medication, muscle relaxants, and medicine for seizures, depression or anxiety). Before using Trimethobenzamide, tell your doctor if you are using any of these medicines.

Trimethobenzamide can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.

Avoid drinking alcohol while you are using Trimethobenzamide. Alcohol may increase drowsiness and dizziness.

Use Trimethobenzamide solution as directed by your doctor. Check the label on the medicine for exact dosing instructions.

• Trimethobenzamide solution is usually given as an injection at your doctor's office, hospital, or clinic. If you will be using Trimethobenzamide solution at home, a health care provider will teach you how to use it. Be sure you understand how to use Trimethobenzamide solution. Follow the procedures you are taught when you use a dose. Contact your health care provider if you have any questions.
• Do not use Trimethobenzamide solution if it contains particles, is cloudy or discolored, or if the vial is cracked or damaged.
• Keep this product, as well as syringes and needles, out of the reach of children and pets. Do not reuse needles, syringes, or other materials. Ask your health care provider how to dispose of these materials after use. Follow all local rules for disposal.
• If you miss a dose of Trimethobenzamide solution and you are taking it regularly, use it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not use 2 doses at once.

Ask your health care provider any questions you may have about how to use Trimethobenzamide solution.

Use: Labeled Indications

Nausea/vomiting: Treatment of postoperative nausea and vomiting; treatment of nausea associated with gastroenteritis

See also:
What other drugs will affect Trimethobenzamide?

Trimethobenzamide may increase the side effects of other drugs that make you sleepy (such as cold medicine, pain medication, muscle relaxants, and medicine for seizures, depression or anxiety). Before using Trimethobenzamide, tell your doctor if you are using any of these medicines.

There may be other drugs that can affect Trimethobenzamide. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

See also:
What are the possible side effects of Trimethobenzamide?

Applies to Trimethobenzamide: intramuscular solution, oral capsule

In addition to its needed effects, some unwanted effects may be caused by Trimethobenzamide (the active ingredient contained in Trimethobenzamide). In the event that any of these side effects do occur, they may require medical attention.

Major Side Effects

You should check with your doctor immediately if any of these side effects occur when taking Trimethobenzamide:

Rare

• Body spasm, with head and heels bent backward and body bowed forward
• convulsions (seizures)
• depression
• shakiness or tremors
• skin rash
• sore throat or fever
• unusual tiredness
• vomiting (severe or continuing)
• yellow eyes or skin

Minor Side Effects

Some of the side effects that can occur with Trimethobenzamide may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common:

• Drowsiness

• Blurred vision
• diarrhea
• dizziness
• headache
• muscle cramps