Home Drug Guide Trimethobenzamide Hydrochloride

Drug Guide

Generic Name

Trimethobenzamide Hydrochloride

Brand Names Tigan, Trimethobenzamide Hydrochloride Preservative Free

Classification

Therapeutic: Antiemetic

Pharmacological: Peripheral dopamine receptor antagonist

FDA Approved Indications

  • Nausea and vomiting

Mechanism of Action

Trimethobenzamide blocks dopamine receptors in the chemoreceptor trigger zone (CTZ) in the brain, reducing nausea and vomiting sensations.

Dosage and Administration

Adult: Typically 200-400 mg orally three times daily. Adjust based on response and tolerability.

Pediatric: Use as per pediatric dosing guidelines; usually 4.5-7.5 mg/kg/day divided into three doses.

Geriatric: Start at lower doses due to increased sensitivity and decreased metabolism; monitor closely.

Renal Impairment: Adjust dose as needed, with cautious use; no specific guidelines, consider renal function tests.

Hepatic Impairment: Use with caution; no specific dosing guidelines available, monitor liver function.

Pharmacokinetics

Absorption: Well absorbed orally.

Distribution: Widely distributed in body tissues.

Metabolism: Primarily hepatic; undergoes hepatic metabolism.

Excretion: Renal excretion of unchanged drug and metabolites.

Half Life: Approximately 6-12 hours.

Contraindications

  • Hypersensitivity to trimethobenzamide or related compounds.
  • Presence of Parkinson's disease or other movement disorders.

Precautions

  • Use with caution in patients with hepatic impairment, in elderly, and in those with a history of seizures. May cause drowsiness or dizziness, caution during activities requiring alertness.

Adverse Reactions - Common

  • Drowsiness or sedation (Common)
  • Dizziness (Often)
  • Dry mouth (Common)

Adverse Reactions - Serious

  • Extrapyramidal symptoms (parkinsonism, dystonia) (Rare)
  • Seizures (Rare)
  • Allergic reactions (rash, urticaria, anaphylaxis) (Rare)

Drug-Drug Interactions

  • Centrally acting sedatives, other CNS depressants, anticholinergic drugs.

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor patient for effectiveness, side effects, and signs of adverse reactions such as extrapyramidal symptoms.

Diagnoses:

  • Risk for falls due to dizziness or sedation.
  • Impaired mobility related to extrapyramidal symptoms.

Implementation: Administer with food if gastrointestinal upset occurs. Monitor neurologic status regularly.

Evaluation: Assess for resolution of nausea and any adverse effects; adjust dosing accordingly.

Patient/Family Teaching

  • Take medication exactly as prescribed.
  • Report any unusual movements, drowsiness, or allergic reactions.
  • Avoid alcohol and CNS depressants while using this medication.

Special Considerations

Black Box Warnings:

  • Avoid use in patients with Parkinson’s disease or history of movement disorders.

Genetic Factors: None established.

Lab Test Interference: May interfere with certain diagnostic tests that evaluate movement disorders.

Overdose Management

Signs/Symptoms: Severe CNS depression, extrapyramidal symptoms, seizures.

Treatment: Supportive care, symptomatic management, activated charcoal if ingestion is recent, and benzodiazepines for seizures.

Storage and Handling

Storage: Store at room temperature away from moisture and light.

Stability: Stable for recommended shelf life, check manufacturer's guidelines.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.