Small Animal Dermatology, 3rd edition

APPENDIX B DRUG FORMULARY 773

Fentanyl, transdermal(Duragesic)

Same as for fentanyl.Transdermal fentanylincorporates fentanyl intoadhesive patches applied toskin of dogs and cats.Studies have determinedthat patches releasesustained levels of fentanylfor 72–108 hours in dogsand cats. One 100

μ

g/h

patch is equivalent to10 mg/kg of morphine q4hIM.

Adverse effects have notbeen reported. However, ifadverse effects are observed(e.g., respiratory depression,excess sedation, excitementin cats), remove patch and, ifnecessary, administernaloxone.

Patches available in sizes of25, 50, 75, and 100

μg/h.

Patch size is related torelease rate of fentanyl.Studies have determinedthat 25

μg/h patches are

appropriate for cats; 50

μg/h patches are

appropriate for dogs10–20 kg. Followmanufacturer’srecommendations carefullywhen applying patches.

25, 50, 75, and 100

μg/h patch.

Dog: 10–20 kg, 50

μ
g/h

patch every 72h.Cat: 25

μ

g patch every

118h.

Firocoxib (Previcox)

Firocoxib is a nonsteroidalantiinflammatory drug(NSAID). Like other drugs inthis class, firocoxibproduces analgesic andantiinflammatory effects byinhibiting the synthesis ofprostaglandins. Firocoxib ishighly selective for COX-2.

GI problems are the mostcommon adverse effectsassociated with NSAIDs andcan include vomitingdiarrhea, nausea, ulcers, anderosions of the GI tract.

Dose for cats has beenreported from only onestudy. Not registered forcats.

Tablets 57 or277 mg.

Dog: 5 mg/kg po, q24h.Cat: 1.5 mg/kg, once.Long-term safety in catshas not beendetermined.

Florfenicol (Nuflor)

Chloramphenicol derivativewith same mechanism ofaction as chloramphenicol(inhibition of proteinsynthesis) and broadantibacterial spectrum. Usein small animals has beeninfrequent.

Use in dogs and cats hasbeen limited; thereforeadverse effects have notbeen reported.Chloramphenicol has beenlinked to dose-dependentbone marrow depression,and similar reactions may bepossible with florfenicol.However, there does notappear to be a risk of aplasticanemia, as forchloramphenicol.

Dose form is approved foruse only in cattle, and thesedoses have not beenthoroughly evaluated insmall animals. Doses listedare derived frompharmacokinetic studies.

300 mg/mLinjectable solution.

Dog: 20 mg/kg q6h po,IM, q6h.Cat: 22 mg/kg q8h IM,po.

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