The purpose of this study is to look at the amount of study drug that gets into the blood stream and how long it takes the body to get rid of it by comparing the results of healthy elderly participants to those of healthy young participants. The tolerability of the study drug will be evaluated. Information about any side effects that may occur will also be collected.

This study will last up to approximately 19 days, not including screening. This study requires either one (Group 2) or two (Group 1) stays at the clinic each of at least four days/three nights. Participants will return for a follow-up seven days after last dose of study drug. Screening is required within 28 days prior to Day 1.

This study is for research purposes only and is not intended to treat any medical condition.

Inclusion Criteria:

• Are overtly healthy males or females, as determined by medical history and physical examination.
• Have a body mass index (BMI) of 19 to 35 kilograms per meter squared (kg/m²) inclusive, at the time of screening.

Exclusion Criteria:

• Have known allergies to lasmiditan, related compounds or any components of the formulation.
• Have an abnormality in the 12-lead electrocardiogram (ECG) that, in the opinion of the investigator, increases the risks associated with participating in the study.
• Show evidence of active renal disease or estimated glomerular filtration rate (eGFR) less than 60 milliliter per minute (mL/min) per 1.73 m².
• Show evidence of or positive serology for human immunodeficiency virus (HIV) infection, hepatitis B or C.
• Are women with a positive pregnancy test or women who are lactating.
• Have a clinically significant abnormality in the neurological examination.
• Have a history of syncope, presyncopy, uncontrolled vertigo, postural dizziness, or at risk for falls, as judged to be clinically significant by the investigator.
• Have orthostatic hypotension with or without dizziness and/or syncope at screening or Day -1 upon repeat testing, or a history of it.

All participants who received at least one dose of study drug.

Up to 10 Days