What medication can be used to increase appetite in an elderly patient?

Medication for Appetite Stimulation in Elderly Patients

Primary Recommendation

Mirtazapine 7.5 mg at bedtime is the first-line pharmacological agent for appetite stimulation in elderly patients, particularly when concurrent depression may be present, with dosing up to 30 mg at bedtime and requiring 4-8 weeks for full therapeutic assessment. 1

Clinical Decision Algorithm

Step 1: Assess for Dementia and Depression Status

If the patient has dementia WITHOUT depression:

• Do NOT use any appetite stimulants - the evidence shows no consistent benefit and potentially harmful side effects outweigh uncertain benefits for appetite and body weight 2, 1, 3
• This recommendation has 89% consensus agreement from Clinical Nutrition guidelines 2
• Focus exclusively on non-pharmacological interventions instead 3

If the patient has depression OR no dementia:

• Proceed to pharmacological options below 1

Step 2: First-Line Pharmacological Treatment

Mirtazapine is the preferred agent because:

• It addresses both appetite loss and potential underlying depression simultaneously 1
• Start at 7.5 mg at bedtime for elderly patients 1
• Maximum dose is 30 mg at bedtime 1
• Bedtime dosing is ideal due to sedating properties 1
• Expected outcomes: mean weight gain of 1.9 kg at 3 months and 2.1 kg at 6 months, with approximately 80% experiencing some weight gain 1
• Full therapeutic trial requires 4-8 weeks to assess efficacy 1

Important FDA-labeled side effects to monitor: 4

• Somnolence (54% vs 18% placebo)
• Increased appetite (17% vs 2% placebo) - this is the desired effect
• Weight gain (12% vs 2% placebo) - this is the desired effect
• Dry mouth (25% vs 15% placebo)
• Constipation (13% vs 7% placebo)
• Dizziness (7% vs 3% placebo)

Step 3: Alternative Agents if Mirtazapine Fails or is Contraindicated

Megestrol acetate 400-800 mg daily: 1, 5

• Approximately 1 in 4 patients will have increased appetite 1
• Approximately 1 in 12 patients will gain weight 1
• Critical safety concerns: thromboembolic events, edema, vaginal spotting, adrenal suppression, and higher rates of deaths compared to placebo 3
• May attenuate benefits of resistance training, causing smaller gains or deterioration in muscle strength and functional performance 1
• Use with extreme caution in elderly patients 1

Dexamethasone 2-8 mg/day: 1, 5

• Faster onset of action, making it suitable for patients with shorter life expectancy 5
• Significant side effects with prolonged use including hyperglycemia, muscle wasting, and immunosuppression 5

Step 4: Monitoring and Reassessment

Regular monitoring is essential: 1

• Reassess benefit versus harm at regular intervals 1, 5
• After 9 months of mirtazapine treatment, consider dosage reduction to reassess need for continued medication 1
• Discontinue mirtazapine over 10-14 days to limit withdrawal symptoms 1

What NOT to Use

Cannabinoids are NOT recommended: 3

• Three small placebo-controlled trials in dementia patients found no significant effect on body weight, BMI, or energy intake 3
• Multiple guidelines conclude evidence is insufficient to support routine use 3
• Cannabinoid administration in elderly patients may induce delirium 3

Flavor enhancing additives should NOT be routinely used to promote food intake 2

Critical Caveats

The one absolute contraindication: Never use appetite stimulants in patients with dementia who do not have concurrent depression - this has strong consensus (89% agreement) from Clinical Nutrition guidelines 2, 1, 3

Before starting any medication: 1

• Investigate treatable causes of poor appetite (oral/dental problems, medication side effects, cholinesterase inhibitors) 3
• Review all current medications that may contribute to poor appetite 1
• Consider temporarily discontinuing non-essential medications 1

Non-pharmacological approaches should be implemented concurrently: 1, 5, 3

• Encourage shared meals with family or other patients to improve intake 1
• Offer smaller, more frequent meals with favorite foods 1
• Provide energy-dense options to maximize nutritional intake 1
• Consider fortified foods and oral nutritional supplements when dietary intake falls to 50-75% of usual intake 1, 3
• Place patients at dining tables rather than isolated in rooms 5
• Provide emotional support, supervision, and verbal prompting during mealtimes 5