Lasmiditan

What lasmiditan is

Lasmiditan binds to the 5-HT1F serotonin receptor. The Reyvow label indicates it for acute treatment of migraine with or without aura in adults. It is not indicated for prevention. It comes as a tablet. The dose comes from the label or the prescriber. Approval differs by country.

Driving and sedation

The label states that lasmiditan may cause significant driving impairment, and advises patients not to drive or operate machinery for at least 8 hours after each dose. It adds three points:

• patients may be unable to judge their own impairment;
• patients who cannot follow this advice should not take it;
• it may cause dizziness and sedation, and should be used with caution with alcohol or other central nervous system depressants.

Results at 2 hours

The label reports two placebo-controlled trials. Each row gives one arm, and arms differ by dose. Patient numbers for pain freedom range from 498 to 544. Patients chose their most bothersome symptom from light sensitivity, sound sensitivity or nausea.

Trial	Arm	Pain freedom	Freedom from most bothersome symptom
Study 1	Lower dose	28.3%	41.2%
Study 1	Higher dose	31.8%	40.7%
Study 1	Placebo	15.3%	29.6%
Study 2	Lowest dose	28.3%	40.8%
Study 2	Middle dose	31.4%	44.0%
Study 2	Highest dose	38.8%	48.7%
Study 2	Placebo	21.0%	33.2%

Other label warnings

• Contraindications. The label lists none.
• Controlled substance. Lasmiditan is Schedule V in the US. In an abuse-potential study, all doses scored higher on drug liking than placebo. The label says to evaluate patients for abuse risk.
• Serotonin syndrome. The label says to stop lasmiditan if it is suspected. Risk may rise with SSRIs, SNRIs, tricyclic antidepressants, MAO inhibitors, dextromethorphan and St. John’s Wort.
• Heart. Lasmiditan has not been well studied in ischemic heart disease. Mean heart rate fell by 5 to 10 beats per minute, against 2 to 5 with placebo, and may fall further with heart-rate-lowering medicines such as propranolol. Blood pressure may rise after a single dose.
• Digoxin. The label does not recommend use with P-gp substrates such as digoxin, where a small rise in level may cause serious toxicity.
• Liver. Lasmiditan has not been studied in severe liver impairment, and the label does not recommend it there.
• Pregnancy and children. There are no adequate human data in pregnancy, and the label says animal data suggest possible fetal harm. Safety and effectiveness in pediatric patients have not been established.

The most common adverse reactions were dizziness, fatigue, paresthesia and sedation. The American Headache Society statement, as reported by MDedge, highlighted driving impairment, sleepiness and possible overuse as risks.

Monthly limit

ICHD-3 was published in 2018, and its section 8.2 does not name lasmiditan. Its general subtype 8.2.8 covers other acute medicines used on 10 or more days a month for more than 3 months. The 2021 American Headache Society statement noted possible overuse with lasmiditan. Its US prescribing information warns that acute migraine medicines used on 10 or more days a month may lead to medication-overuse headache (section 5.4).

The medication days counter and Aurora do not count lasmiditan against an ICHD-3 limit. This does not mean any frequency is safe. Details are under gepants and lasmiditan.

In a headache diary

Count the days you take it. The label warning uses a 10-day figure, and a doctor can read your count against it. Besides pain at 2 hours, record your most bothersome symptom, then dizziness or sleepiness and how long they lasted. Note the dose time, since the 8-hour driving advice runs from it.