Famciclovir dosage

mcoon

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For an adult cat with a herpes upper respiratory infection, would anybody know the recommended dosage for an acute outbreak?  e.g.  x mg / kg or for a cat that is 18 pounds?

Thanks much
 

white shadow

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This is verbatim from Plumb's Veterinary Drug Handbook, 7th edition:   [ ] represents my own insertions.....I have not included references given
Doses

CATS:

For feline herpes virus (FHV-1)

Note: There is a considerable amount of uncertainty at present how to dose cats with famciclovir, but because the drug looks promising, there will be more data forthcoming.

a)There is a wide range of doses used; author's choice: 125mg (total dose) PO [by mouth] 2-3 times a day.

b) For adjunctive treatment of FHV-1 rhinotracheitis: 31.25mg (1/4 of one 125mg tablet) PO every 12 hours for 14 days. Has not been evaluated for long-term therapy.

c) For chronic, recurrent and/or severe herpes viral infection: Dose range is variable! Kittens: 1/8 of one 125mg tablet once daily for two weeks; adult cats: 1/4 of one 250mg tablet once daily for three weeks.

d) 1/4 of one 125mg tablet twice daily for 10-14 days; may continue once daily for up to 30 days

e)For adjunctive treatment (with interferon and lysine) of herpes virus-associated ulcerative facial dermatitis & stomatitis: 125mg every 12 hours.
While your question was restricted to dosing, I'll add the following in case you're unaware:
 Contraindications/Precautions/Warnings

....It should be used with caution (and dosage adjustment) in patients with renal dysfunction  [kidney disease/insufficiency]

Adverse Effects

Adverse effects in acts are not well documented, but the drug appears to be tolerated quite well when used for up to 3 weeks. At doses of 90mg/kg every 8 hours, anorexia and polydipsia have been noted in some cats.

In humans, famciclovir can cause nausea, vomiting, diarrhea, and headache. Neutro has been reported and renal failure can occur, particularly  when doses are not adjusted in patients with renal dysfunction.
Hope that helps !
 
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mcoon

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Excellent!  Thanks much!!
 

andrew927

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dear sir, i would appreciate your suggestion on this compared with pfizer's zithromax with ingredient of azithromycin. I have fed the latter one to my cat and he was becoming not active, not having appetite and always wanted to vomit (nothing out) i stopped that immediately and eventually he recovered from that sign.

the reason i treated him is that he is having mucus(yellow/green) after he sneezed. 

the other cat also fed with the zithromax, the symptom was cured for a while and eventually coming out again. i believe this medicine can't cure it.

this is why i am trying to search for others. i came up with 2 different. synulox and famciclovir

the other suggested to use synulox. 

may i know which one i should use better?

please kindly advise.
 

stephanietx

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Famciclovir is an anti-viral.  Feline herpes is a viral infection. Zithromax is an antibiotic  that treats bacterial infections.   
 
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