How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Dr. Michael Salkin Your Own Question
Dr. Michael Salkin
Dr. Michael Salkin, Veterinarian
Category: Cat Veterinary
Satisfied Customers: 30274
Experience:  University of California at Davis graduate veterinarian with 45 years of experience.
Type Your Cat Veterinary Question Here...
Dr. Michael Salkin is online now
A new question is answered every 9 seconds

My 4 1/2 months old cat just ate 1 500 mg tab of

Customer Question

My 4 1/2 months old cat just ate 1 500 mg tab of valacyclovir. Is this poisonous for him?
Submitted: 1 month ago.
Category: Cat Veterinary
Expert:  Dr. B. replied 1 month ago.

Hello & welcome, I am Dr. B, a licensed veterinarian and I would like to help you with your wee one today.

How long ago did he eat this?

How much does he weigh?

How is he just now?

Customer: replied 1 month ago.
15-20 minutes ago. Just over 4#. Seems fine.
Expert:  Dr. Michael Salkin replied 1 month ago.

it isn't clear to me why a new expert was requested. If you're waiting for Dr. B, instead, my apologies for entering this conversation.

Valacyclovir is uniquely toxic to cats. In one study of valacyclovir in cats when dosed at 27 mg/lb every 6 hours by the 6th to 9th days lethargy and dehydration were apparent. Histopathologic changes involving their kidneys were noted as well and so this antiviral drug isn’t recommended for cats. Your cat ingested a very high dose of 125 mg/lb. Inducing emesis with 5 mL per 5 lbs of body weight (4 mL for him...a bit less than a measuring teaspoon) with 3% hydrogen peroxide by means of an eyedropper placed between his cheek teeth and cheek can be prudent but peroxide isn’t reliably effective in inducing emesis in cats. If possible, it’s preferable to have a vet induce emesis with an injection of an emetic. Please respond with further questions or concerns if you wish.