l-lysine — FDA Animal & Veterinary Adverse Event (ADE) Reports
Source: openFDA animalandveterinary/event.json, the FDA Center for Veterinary Medicine (CVM) adverse event report database. Data pulled 2026-08-16. Counts are report-level: one report may list multiple reactions and multiple animals, so figures are not additive and do not imply causation. "l-lysine" is a name as filed in the drug active-ingredient field of these reports (may be a generic ingredient or a product/brand name as reported).
Total reports
l-lysine: 99
Reports by species (top entries)
- Cat 91
- Dog 5
- Turkey 2
- Horse 1
Top reported reactions (VEDDRA terms, top entries)
- Lethargy (see also Central nervous system depression in 'Neurological') 15
- Vomiting 14
- Ocular discharge 11
- Weight loss 11
- Anaemia NOS 10
- Emesis 10
- Anorexia 9
- Behavioural disorder NOS 9
- Other abnormal test result NOS 9
- Fever 8
Source JSON: pdf-raw/ade/ade_active_ingredients_2026-08-16_b1.json (openFDA animalandveterinary/event.json, pulled 2026-08-16).