The purpose of this study is to compare two different formulations (test & reference) of LY3471851 in healthy participants. This study will compare how much of each formulation gets into the blood stream and how long it takes the body to remove it. Information about any side effects that may occur will also be collected. Participants will remain in the study for about 12 weeks, after receiving the study drug that is LY3471851.

Inclusion Criteria:

• Participants who are overtly healthy as determined by medical history and physical examination
• Have body weight greater than 45 kilograms (kg) and body mass index within the range 18.0 to 32.0 kilograms per square meter (kg/m²)
• Male and female participants must agree to adhere to contraceptive requirements

Exclusion Criteria:

• Have an abnormality in the 12-lead electrocardiogram (ECG), vital signs, or both
• Have had symptomatic herpes zoster within 3 months prior to screening
• Have a known allergy or hypersensitivity to levocetirizine
• Intend to use prescription or nonprescription medication within 14 days or 5 half-lives prior to dosing
• Have received treatment with biologic agents within 3 months or 5 half-lives prior to dosing
• Smoke more than 10 cigarettes or other tobacco products per day before study entry
• Are pregnant or breastfeeding, or intend to become pregnant or breastfeed during the study