Forgot dog's phenobarbitone: Should I give it or skip the dose?

If you are suspicious that Tootsie did not receive much, if any, of her evening phenobarbital dose, I would consider just giving her an extra half of a dose, or 0.35 ml in this case. However, if there is a chance that she received most of the dose, it would be best to skip this dose and administer her next dose at the normal time.

Hello and thank you for contacting Petco Pet Education Center, formerly Petcoach. Opie will be fine. He may show signs of sedation, lethargy and sleepiness for 8-12hrs but there should not be any more worrying signs. Please, continue with the next dose of phenobarbital as normal.

Hello. Phenobarbital can be absorbed very quickly, so it possible that some has already entered the bloodstream. If Luna's seizures have been well controlled up to this point, then missing one dose will not be harmful. Just redose at her next normal scheduled time. If she continues to vomit or act unwell, see your vet quickly to have her liver & phenobarb levels checked to make sure all is well. Thanks for using Petco Pet Education Center, formerly Petcoach.

Unfortunately you do not mention the weight of the dog which received the phenobarbital. A normal dose would be 2-3 mg of phenobarbital per kg (2.2 lbs) of dog. If your dog is much smaller than 6 kg (13lbs) then you need to watch it closely for the next few hours. Your dog will most likely get very sleepy. If it sleeps so deep you cannot wake it up or if you think it is not breathing properly, you will need to take it to the emergency room. If the ingestion occurred within the last hour and the amount ingested was a significant overdose, you should consider taking your dog to the emergency vet so that vomiting can be induced to get the drug out of the system. Also if your dog has liver disease, please take it to the emergency clinic.

I probably would not give another dose if he spit up the material 45 minutes after receiving the phenobarbitol, especially if you are not sure it was actual vomit. Monitor for additional signs and call your vet if you have any concerns. So sorrry that Harley has lung cancer.

No. Phenobarbital needs to maintain specific blood levels and the half life of the medication is 12 hours. That’s why it is dosed at that interval. You must also be careful not to over dose the medication. If you have having trouble with control of Tootsie’s seizures, I recommend to call your veterinarian. There are other medications that can be given in combination with or in substitution for phenobarbital. Follow the instructions on the label with this medication. I hope this helps and please feel free to post any additional questions.

Phenobarbital therapy in dogs is begun at 2 to 4 mg/kg twice daily. So for a 33kg dog that would mean 66 to 132 mg twice a day. We always try to start low and increase if needed but he was essentially really underdosed in the beginning with taking 30mg twice a day. He is now on a more appropriate dose. Sedation is normal when therapy is initiated but once the dog's body gets used to the drug (after about 2 weeks) he should become more like himself. If you are really worried, you can ask the vet to run a phenobarbital level blood test to see if his dosing is too high and it can be adjusted accordingly. Please be aware that dogs will never be completely seizure free even while on anti-seizure medication. Breakthrough seizures are common but they should be pretty infrequent. If he continues to seizure or does not do well on the phenobarbital there are other medication options so please work closely with your vet.