My non sick cat ate the sick cats pill

Long story short I think my well cat at 12.5 mg of my sick cat's phenobarbital. I am not sure so the sick may miss a dose and the well cat may have ingested it. Comments please on either scenario? There is no one to call here as I live in the Caribbean. HELP

Aww thats not good! Im going to look some stuff up for it! BRB!

So far it looks like IF the cat has a bad reaction slow breathing can occur, and sedation, any of those??

I left sick cat's med in a spoon of food. Darling daughter let well cat in who was been on a 3 day walk about. I did not know. We went out at 6:30. Well cat is ok but very sedated it seems but purring and breathing ok. Sick cat who may not have had her med is bouncing off the walls. Ugh...I think well cat ate it and sick cat did not but I will give sick cat her regular AM dose instead of giving her a pill in case she did eat it (but I am sure she did not)..welcome to my world..

I would watch carefully for any changes in eating, drinking, and sleeping habit--if you notice anything new, call the vet (ER vet if after hours) and explain what happened. According to the Merck Vet Manual, the most common signs of toxicity are "sedation, ataxia, respiratory depression, coma, loss of reflexes, hypotension, and hypothermia."

http://www.merckvetmanual.com/mvm/in.../bc/214028.htm