Help for suspected Famotidine/Pepcid overdose

I've been taking care of my Kidney Disease/ Diabetic cat for the past 4 years, we've had our share of spills and triumphs during that time, mostly triumphs. Normally my cat is acting like a little kitten! However, this weekend while I was away she began throwing up her food and when I returned she was listless and weak. Her blood tests from a few days prior came back excellent, best they had ever been, so my vet was as confused as I was. I am still waiting on the results of a urine test as well. However, in my enthusiasm to help, I believe I may have administered her too much Famotidine, because she is showing symptoms like dizziness, nausea and lack of appetite. She walks like she can barely stand, urinates on and off out of the litterbox and hovers over her food without eating. Last night she ate quite a lot with the help of an appetite and nausea pill, but this morning she was back to the same. I'm hoping that appetite and nausea pills will again help her feel better and get some food in her, but from what I can see online it takes 2-3 days for famotidine to exit her system. 

It's upsetting to see her in pain and to have exhausted my options to no avail! I was wondering if anyone had some experience with this, I'm not sure what else to do!

Best,

Kim

Moomie said:

 
Best,

Kim

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The standard dose is 2.5mg (1/4 of a 10mg pill) once daily.  The ASPCA poison control hotline is VERY experienced and handles 100's of calls a day.       ASPCA Poison Control Hotline: Tel: (888) 426-4435, aspca.org/pet-care/animal-poison-control  

Thank you, Steven. I would call the hotline but it charges 60$, I called the regular human poison control hotline but they were not very helpful and didn't ask me any questions, just said to take her to the vet. I called them yesterday and left a message with the doctor who sees her, and then monitored her through the night. This morning I gave a pill for nausea and another for appetite, and like the night before she ate about half. By noon today she was laying more comfortably more often, and acting more alert (she went over to her window and watched the cars go by with interest for about ten minutes) she is walking around a little faster and more often. I know everybody's first advice would be to take her to the doctor, but I'm sadly not in the financial position to be able spend 300-500 dollars on a doctors visit this month. On top of that, her situation, what ever it is, seems to be improving, if slowly. Still, there is nothing I would rather do more. Please understand, and let me know if there is anything else I could be doing.

Here is more info about her intake of the drug: I bought her famotidine online, and forgot that the dosage was different (20 mg, as opposed to 10mg for her former pills) and was cutting it the same way, so, for the past 3 months she had been receiving twice her normal dosage at 10mg. (her normal dosage is 5mg, which from the looks of it is already high) Before the symptoms began, I had been out of town and the person caring for her (a friend) did not know how to administer her normal dosage of famotidine and so she went without it for 2 days. When I arrived in the morning, my cat was throwing up anything that she ate or drank. I gave her Subcutaneous fluids and what I mistakenly thought was her usual dosage (was actually 10 mg) and later that day when she still could not eat I gave her another 10mg pill. That's when the symptoms began (Monday).

Moomie said:

Thank you, Steven. I would call the hotline but it charges 60$, I called the regular human poison control hotline but they were not very helpful and didn't ask me any questions, just said to take her to the vet. I called them yesterday and left a message with the doctor who sees her, and then monitored her through the night. This morning I gave a pill for nausea and another for appetite, and like the night before she ate about half. By noon today she was laying more comfortably more often, and acting more alert (she went over to her window and watched the cars go by with interest for about ten minutes) she is walking around a little faster and more often. I know everybody's first advice would be to take her to the doctor, but I'm sadly not in the financial position to be able spend 300-500 dollars on a doctors visit this month. On top of that, her situation, what ever it is, seems to be improving, if slowly. Still, there is nothing I would rather do more. Please understand, and let me know if there is anything else I could be doing.

Here is more info about her intake of the drug: I bought her famotidine online, and forgot that the dosage was different (20 mg, as opposed to 10mg for her former pills) and was cutting it the same way, so, for the past 3 months she had been receiving twice her normal dosage at 10mg. (her normal dosage is 5mg, which from the looks of it is already high) Before the symptoms began, I had been out of town and the person caring for her (a friend) did not know how to administer her normal dosage of famotidine and so she went without it for 2 days. When I arrived in the morning, my cat was throwing up anything that she ate or drank. I gave her Subcutaneous fluids and what I mistakenly thought was her usual dosage (was actually 10 mg) and later that day when she still could not eat I gave her another 10mg pill. That's when the symptoms began (Monday).

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If she is microchipped with home again its either free of very very cheap.   But i'm glad she's improving.

Well, just to set your mind at ease a little bit, with my 2nd kidney cat, our Vet had us give him Pepcid A/C TWICE a day, not once, for a total of 5 mg per day, as you were originally giving.  I found the following symptoms of Famotidine overdose on Petmd.com:

Overdose of Famotidine is rare but symptoms of an overdose may include:

• Vomiting
• Restlessness
• Redness of the mouth and ears
• Rapid heart rate
• Collapse

Since your regular Vet isn't available, is there not a different Vet at the same clinic who you could simply ask the question of?  If not, then if she seems to be getting better, and you can't afford to call poison control, then just keep a close eye on her and take her to another Vet if things get worse. 

Sometimes the Pepcid A/C does not do the trick when they are vomiting.  Again, my 2nd kidney cat needed Ranitidine THREE times a day as well.  With that the dosage is very specific to the weight of the cat.  I think he got 1/8 of a pill 3 times a day. 

Are you familiar with this website for kidney cats  This has been my "go to" for all three of my kidney cats:  http://www.felinecrf.org/nausea_vomiting_stomach_acid.htm

Moomie,

Most cats with mild (or even at the cusp of severe) renal disease are prescribed 2 to 5 mg pepcid ONCE daily.  Other doses are prescribed according to actual physical needs as determined and monitored regularly by the vet.

You in fact, have most likely been giving too much pepcid - your posts are a bit confusing between the months and last weekend of the actual doses you've been giving. You also did not state which brand, type of pepcid (or famotidine) you've been giving.

Equally as important are the potential side effects of giving pepcid with anti-nausea AND appetite stimulant drugs - pepcid alone can cause numerous side effects, some of them severe (CNS, respiratory, muscle, etc) - dizziness and inappetence are only a couple of many side effects.  Combined with anti-nausea and appetite stimulant drugs, the side effects can be more severe.

Please, call the clinic NOW, speak to any vet available and tell them you've been giving over the prescribed dose of pepcid (tell them for how long) and make sure you also tell them you're giving anti-nausea and appetite stimulant medications (tell them how often).  I personally would recommend ceasing the pepcid entirely until she has had a chance to clear the excess out of her system.  Then the vet may suggest resuming a smaller dose.

Despite your impression of her getting a little bit better, you don't know what her renal and kidney values are since she's been getting much more pepcid - these should be checked right away, or, as your vet advises.  It's not a hundreds or thousands-dollar bill, it's a blood recheck to ensure her values are good and not hampered due to the increased pepcid doses.  The price of the blood work is worth it to determine she is in fact going to be ok and continue to do well.

Don't wait for your regular vet to get back to you, call the clinic and talk to ANY of the vets there, or, call an emergency vet for advise.

By the way, for anyone else reading, vitamin B12 injections MAY be contraindicated when using pepcid, use only at your vet's discretion and advice (while B12 is essentially harmless at the right dose, it indeed can be enhanced OR ineffective depending on what other medications the patient is receiving).