Circadian Rhythm Medication Dosing
I cannot provide specific dosing recommendations because "Circ" is not a recognized medication name in the available evidence or standard pharmacological references.
Clarification Needed
The term "Circ" does not correspond to any approved circadian rhythm medication in current clinical practice. If you are referring to a medication for circadian rhythm sleep-wake disorders, the most likely candidates based on the available evidence are:
Tasimelteon (Hetlioz)
For Non-24-Hour Sleep-Wake Disorder, the FDA-approved dosing is 20 mg taken orally one hour before bedtime at the same time every night, without food. 1
- Administration timing is critical: Take at the same time every night to maintain circadian alignment 1
- Take without food to ensure proper absorption 1
- If a dose is missed: Skip that dose and resume the next scheduled dose—do not double up 1
- Onset of effect: Drug effect may not occur for weeks to months due to individual differences in circadian rhythms 1
Important Clinical Considerations
Avoid combining tasimelteon with strong CYP1A2 inhibitors (e.g., fluvoxamine) due to potentially large increases in drug exposure and adverse reactions. 1
Avoid combining with strong CYP3A4 inducers (e.g., rifampin) as they significantly decrease tasimelteon exposure and reduce efficacy. 1
Beta-adrenergic receptor antagonists (e.g., metoprolol, acebutolol) may reduce tasimelteon efficacy when administered at night, as they inhibit melatonin production via beta-1 receptor blockade. 1
Common Adverse Effects
- Headache (17% vs 7% placebo) 1
- Elevated alanine aminotransferase (10% vs 5% placebo) 1
- Nightmares/abnormal dreams (10% vs 0% placebo) 1
- Somnolence warning: Limit activity to preparing for bed after taking tasimelteon, as it can impair mental alertness 1
Alternative Interpretation
If "Circ" refers to a different medication or abbreviation used in your institution, please provide the complete medication name for accurate dosing guidance. The American Academy of Sleep Medicine guidelines address circadian rhythm disorders with light therapy, melatonin, and behavioral interventions, but "Circ" as a standalone medication name does not appear in published guidelines 2, 3.