Armodafinil: Adult Dosing, Contraindications, Precautions, and Adverse Effects
Armodafinil is dosed at 150-250 mg once daily for narcolepsy and obstructive sleep apnea (taken in the morning), or 150 mg taken before the start of night shifts for shift work disorder, with elderly patients requiring lower starting doses of 100 mg. 1
Adult Dosing Guidelines
Standard Dosing by Indication
- Narcolepsy and OSA: 150-250 mg once daily in the morning 2, 3
- Shift Work Disorder: 150 mg taken approximately 1 hour before the start of the night shift 3
- Flexible dosing range: 100-250 mg daily based on clinical response 4
Special Population Adjustments
- Elderly patients: Start at 100 mg daily with close monitoring due to potential increased sensitivity 1
- Pharmacokinetic considerations: Peak plasma concentrations occur approximately 2 hours after administration when taken fasting; food delays peak by 2-4 hours but does not affect overall bioavailability 5
- Steady state: Achieved within 7 days of once-daily dosing, with systemic exposure 1.8 times that of single-dose administration 5
Contraindications and Critical Precautions
Absolute Contraindications
- Pregnancy: Contraindicated based on animal data showing fetal harm and a 2018 pregnancy registry report demonstrating higher rates of major congenital anomalies in children exposed in utero 2, 1
Major Precautions
- Hormonal contraception failure: Armodafinil reduces the effectiveness of oral contraceptives, requiring alternative birth control methods during treatment and for one month after discontinuation 2, 1
- Controlled substance status: FDA Schedule IV due to potential for abuse or dependency 1
- Cardiovascular monitoring: Monitor blood pressure and heart rate, particularly in patients with cardiac history; modest increases (3.6/2.3 mm Hg BP, 6.7 bpm heart rate) typically occur by month 3 of treatment 6, 7
- Psychiatric symptoms: Monitor for anxiety, mood changes, and other psychiatric effects 6
Common Adverse Effects
Most Frequent Adverse Events
- Headache: The most commonly reported adverse event, occurring in approximately 14-25% of patients (up to 50% in some studies) 6, 5, 4, 7
- Upper respiratory tract infections: Commonly reported 6
- Dizziness and nausea: Frequently occurring adverse events 6, 5
- Sinusitis and somnolence: Additional documented adverse events from clinical trials 6
- Nasopharyngitis: Reported in 17% of patients in long-term studies 7
- Insomnia: Occurs in approximately 14% of patients 7
Clinical Monitoring Priorities
- Focus monitoring on documented adverse events, particularly headache, which is the predominant side effect 6
- Tinnitus should NOT be considered an expected adverse effect of armodafinil therapy 6
- Serious but rare events: Severe skin reactions, psychiatric symptoms, and delirium/agitation have been reported with modafinil (the racemic compound) 2
Efficacy and Tolerability Profile
Clinical Response Rates
- In 12-month open-label studies, 80% of patients with treated OSA and 84% of patients with narcolepsy were rated as at least minimally improved on the Clinical Global Impression of Improvement scale 4
- 98% of shift work disorder patients showed improvement in sleepiness during night shifts 4
- Discontinuation due to adverse events occurred in only 13% of patients during the initial 12-month period 4, 7