Why capsule ingestion is an emergency for your 6 kg cat
A whole capsule delivers a sudden, concentrated dose—unlike gradual exposure from powder mixed in food. The casing may have dissolved quickly in their stomach, releasing all the 5-HTP at once. At this weight, even one standard 50mg capsule can overwhelm their system within hours.
Search everywhere for more dropped capsules right now. They often bounce under appliances or get stuck in carpet fibers. Use a flashlight to check shadows—cats sometimes play with pills like toys before eating them. Secure other supplements in childproof containers, not just bathroom cabinets.
The critical difference between exposed and unexposed cats
Your two unaffected cats need no treatment unless you saw them chewing capsules. 5-HTP doesn't spread through casual contact—they'd have to ingest it directly. But separate all cats immediately, as stress from one animal's symptoms can trigger unusual behaviors in others.
Monitor the unexposed cats' water bowls. Sometimes a capsule breaks open when dropped, leaving bitter powder residue that makes cats drink excessively. Sudden increased thirst in any cat warrants a vet call, as it could indicate secondary exposure.
What to gather before calling the vet
Note the exact time you found the capsule missing. This helps the vet predict when symptoms might peak. If the supplement was part of a multi-blend, photograph the full ingredient panel—many combine 5-HTP with caffeine-like substances that multiply the danger.
Prepare to describe your cat's normal behavior baseline. Vets need to know if they're typically anxious or vocal to distinguish pre-existing traits from new symptoms. Mention any recent changes in diet or medication, as some interact unpredictably with serotonin modifiers.
Why you shouldn't wait for visible symptoms
Neurological damage can occur before obvious signs appear. Subtle early clues include excessive whisker twitching, sudden interest in running water, or refusing favorite treats. These often precede full tremors by 1-2 hours in cats.
Block off high spaces in your home. Affected cats may try to climb excessively or leap unpredictably due to disorientation. Place their carrier near the door now so you're ready to leave immediately if their condition changes.
The step-by-step response, from the first minute to the vet visit, is in our 5-HTP & Herbal Supplements emergency guide.