Alternative Antiemetic Medications for Older Adults
For older adults with nausea, haloperidol, phenothiazines (such as prochlorperazine), scopolamine, dronabinol, and olanzapine are effective alternatives to ondansetron or metoclopramide. 1
First-Line Alternatives
Phenothiazines
- Prochlorperazine: 5-10 mg orally or IV every 6-8 hours 1
- Effective for general nausea management
- Lower risk of extrapyramidal symptoms than metoclopramide
- Monitor for sedation and orthostatic hypotension in older adults
Haloperidol
- Dose: 0.5-2 mg orally or IV every 8 hours 1, 2
- Particularly effective for opioid-induced nausea
- Start at lower doses in elderly patients (0.5 mg)
- Advantage of minimal anticholinergic effects compared to other options
Second-Line Alternatives
Olanzapine
- Dose: 2.5-5 mg orally daily 1
- Especially helpful for patients with bowel obstruction
- Lower starting dose (2.5 mg) recommended for older adults
- Blocks multiple receptors (dopamine, serotonin, histamine) providing broad antiemetic coverage
Scopolamine
- Transdermal patch: 1.5 mg patch applied behind ear every 72 hours 1
- Useful for motion-induced or vestibular causes of nausea
- Caution regarding anticholinergic side effects in elderly (confusion, urinary retention)
Cannabinoids
- Dronabinol: 2.5 mg orally twice daily, titrate as needed 1
- FDA-approved for chemotherapy-induced nausea
- May be particularly useful when other antiemetics have failed
- Start at lower doses in elderly patients
Corticosteroids as Adjuncts
- Dexamethasone: 4 mg orally or IV daily 1
- Particularly effective when combined with other antiemetics
- Short courses (3-5 days) minimize side effects
- Avoid prolonged use in elderly due to risk of delirium, hyperglycemia
Special Considerations for Older Adults
Risk Factors to Consider
- Assess for drug interactions with current medications
- Consider renal and hepatic function when selecting agent and dose
- Start with lower doses and titrate slowly
- Monitor for extrapyramidal symptoms, which occur more frequently in elderly
Monitoring
- Evaluate response within 24-48 hours after starting therapy
- Assess for adverse effects, particularly sedation, confusion, and extrapyramidal symptoms
- Consider medication rotation if initial therapy is ineffective or poorly tolerated
Cautions and Contraindications
- Phenothiazines and haloperidol: Use with caution in patients with Parkinson's disease or dementia with Lewy bodies
- Olanzapine: Monitor for excessive sedation and metabolic effects
- Scopolamine: Avoid in patients with narrow-angle glaucoma or prostatic hypertrophy
- Dronabinol: Use cautiously in patients with cardiovascular disease or history of psychiatric disorders
By selecting appropriate alternatives to ondansetron and metoclopramide based on the patient's specific condition and comorbidities, effective nausea control can be achieved in older adults while minimizing adverse effects.