Hi,

I was wondering if it is normal for a Horsfield tortoise to be very lethargic (to the extent of falling asleep when bathed) following a dose of Panacur worming treatment.

The tortoises owner was advised to seek vetinary advice as her three year Horsfield had regurgitated food on a couple of occasions. Worms were identified and the vet appears to have given a single, large dose of Panacur as the full treatment. I've found a similar thread on this forum for a vet doing the same, stating that a single large dose was a suitable treatment. I'm trying to persude the person to ask the vet about another course of Panacur in three weeks or so. What also worries me is that the vet attempted to administer the Panacur, the tortoise regurgitated it and the person was asked to visit the next day for another attempt. This was administered by stomach tube so a percentage of the initial dose could have stayed down. Is it possible to easily overdose a tortoise with Panacur? Could this cause the extreme lethary ( the tortoise has not eaten and has only been observed sipping tiny amount of water during its regular bathing) or is the lethary a normal result of the worming treatment with Horsfields?

Any advice or previous experience would be greatly appreciated and passed onto the owner.

As usual thanks in advance, one day I'll post on a happy topic!

Dave.

Hi Dave

This doesn't sound normal to  me either.  It could be, of course, that the worms are still needing to be passed, and also that the tortoise is very anaemic.  I'm not sure about overdosing - perhaps this is a question for our on line vet so I'll ask him to take a look at your post.

Helen

Helen

Hi Dave

I sent your message to Kevin and as he has trouble getting online he has asked me to post the message below on his behalf.

Helen

Panacur is a wormer called fenbendazole. This drug class disrupts tubule formation on worms leading to their death. However at high doses it interferes with this process in the host species. Thus toxic effects are seen and can include bone marrow suppression (and hence immunosuppression) and gastrointestinal ulceration amongst others. Toxic dosages reported have been in the region of 250 - 400 mg/kg. There is a paper reproting this in feas vipers. The signs are often called 'radiomimetic'. Lethergy and death are signs that  could be seen.
 
I do not advocate routine worming of tortoises, but instead insist on routine testing for parasites. Dosages used typically are 100mg/kg as a single dose repeated two weeks later given by stomach tube. However greater effectiveness is acheived by lower dosages (25mg/kg) given daily over a three day period and reducing any risk of toxicity. The downside is three trips to the vet and increased expense. Dosing may need to be repeated a month later and it is best to check the faecal egg output of any tortoise to ensure that the worms have been eliminated, particularly prior to the tortoise going onto a particulate substrate or into the garden. High worm burdens can be seen that can lead to lethergy and anorexia. Accurate weighing of the tortoises and calculations of the drug is important to minimise any risks.
 
The reflux reported would have reduced the dosage and using well mixed suspensions of fenbendazole should limit this as well.
I suspect the lethargy is related to underlying disease (regurgitation is not a good sign in tortoises) and that further treatment and diagnostics are required. If worms were identified then they would have needed to have been a significant burden to lead to regurgitation otherwise this may be a red herring and the animal has other issues that need addressing.

Kev

Helen,

Thankyou so much for this and please pass on my thanks to Kevin. It is much appreciated. I now have to persuade the owner that further investigation is required. I am not sure that the tortoise is attending a specialist vet! I have a couple of recommendations as the owner is also in London.

Thanks again,

Dave.

No problem Dave, I'll pass your message on and please do keep us informed on any further developments with this tortoise. 

Helen

Thanks Helen,

Will keep you up to date.

Dave