Can a dewormer, given to a 3 week old kitten that is underweight, cause it to become ill or even die?
Well, it is ALWAYS possible that an animal could have a reaction to any medication (or food or anything else for that matter) that could cause serious illness or death. However, that would be quite rare. Most over the counter dewormer products are EXTREMELY safe and even with overdosing there are typically few (if any) side effects. That being said, most dewormers are not to be used in kittens under 4 or 6 weeks of age. Side effects are usually that of vomitting and/or diarrhea. If the medication was Drontal, it is safe in kittens as young as 2 weeks old at the recommended dosage.
Reply to SLH's Post: I was fostering the kitten for the humane society. He was brought in on Wednesday covered in fleas so I took him home to care for him. They gave me some dewormer yesterday to give him (they deworm at 2 weeks, 4 and 6). Today he didn't seem right (he couldn't really walk anymore, but he didn't have any diarrhea or vomiting) so I rushed him to the emergency vet. I ended up having to put him down because the vet said he wasn't in good shape. He had cardiac arythmea, an eye infection and he was already underweight. I've been really upset in losing the little guy, but it's even sadder to think that the dewormer aided in it. Before Saturday he seemed to be doing ok, but was still underweight. Do you think it aided in is downfall or was he probably already going downhill?
I really have to think that it most likely was not the dewormer. If they worm at 2, 4, and 6 weeks then they are using something quite safe for that(most likely the Drontal) The poor little guy had probably had a tough row to hoe and was on his way down anyway. I applaud you for making the right decision for him and I sympathize with you for the grief you feel now.
Former Vet Tech student, raised animals for 30+ years