Page 1538 - Clinical Small Animal Internal Medicine

1476 Section 12 Skin and Ear Diseases

Table 167.3 Selection of ear cleaner based on the type of discharge present
VetBooks.ir

Type of Moderately waxy/ Mildly waxy/ Mucopurulent/
discharge Thick and waxy purulent purulent hemorrhagic

Typical Sterile ceruminous otitis Malassezia otitis Gram‐positive otitis Gram‐negative otitis
findings
The waxier the discharge, the greater the ceruminolytic properties of the ear cleaner to emulsify the wax

The more mucopurulent the discharge, the more aqueous the cleaner to break down mucus and flush the ear

Table 167.4 Topical antibiotic therapy for use in otitis externa and media

Order of use Drug Indications Safety in otitis media
First‐line drugs Framycetin Gram‐positive and many Unsafe
gram‐negative bacteria
Neomycin Gram‐positive and some Unsafe
gram‐negative bacteria
Fusidic acid Gram‐positive bacteria Unsafe
Florfenicol Gram positive bacteria Unsafe
Second‐line drugs Gentamicin (may be Gram‐positive and many Proprietary veterinary products unsafe;
used as first line where gram‐negative bacteria aqueous solutions appear safe at
neomycin unavailable) 2.0–4.0 mg/mL
Polymyxin Excellent Gram‐negative activity Unsafe
Enrofloxacin Fluoroquinolones have excellent Proprietary veterinary products unsafe;
Ciprofloxacin Gram‐negative and ‐positive aqueous solution mixed with EDTA‐tris
activity. Their use is best appears safe. Enrofloxacin used at
Marbofloxacin reserved for gram‐negative 0.5–1.0 mg/mL. Marbofloxacin used at
Orbifloxacin infection 0.1–0.3 mg/mL
Silver sulfadiazine Broad spectrum; excellent Safety of veterinary product unknown;
activity against Pseudomonas 1% cream mixed with sterile water
spp. diluted 1:10 appears safe
Third‐line drugs best Amikacin Resistant gram‐negative bacteria Ototoxic – off‐license use of aqueous
reserved for severe solution of 30–50 mg/mL
gram‐negative Tobramycin Resistant gram‐negative bacteria Ototoxic – off license use of aqueous
infection on the solution of 8 mg/mL
basis of culture and
sensitivity Carboxypenicillins Resistant gram‐positive bacteria Ototoxic – off‐license use of aqueous
solution of 10 mg/mL
All aqueous solutions constitute off‐license use of these drugs.

All therapeutic protocols should include regular and cytologic resolution of the infection has been
follow‐up examinations every 7–14 days. Cytology achieved. Long‐term management should include regu-
should be performed at each visit and antimicrobial lar ear cleaning with an appropriate product and therapy
therapy should be continued until a complete clinical of the underlying primary cause.