Fenbendazole 50mg/kg PO SID +/- Metronidazole 25mg/kg BID for 5 days
If treatment + bathing does not eliminate infection, extend for additional 10 days
Treat same household species with one course of therapy
Monitoring:
Recheck fecal flotation (ZnSO4) 24-48h after treatment ifstill clinical
Control:
Bathe on first and last day of treatment (especially muzzle, paws, perineum)
Remove feces immediately and dispose with municipal waste (cysts immediately infective)
Environmental areas (e.g., soil, grass, standing water) are difficult to decontaminate, but surfaces can be sanitized by steam-cleaning or use of commercially available disinfectants. Allow surfaces to dry thoroughly after cleaning.
Heartworm Disease
Diagnosis:
4Dx positive → confirm with repeat 4Dx + Microfilaria Filter Test
Treatment:
Day 1-28:
Apply heartworm preventative
If microfilaria detected, pre-treat with anti-histamine and glucocorticoid (if not already on prednisone) and monitor for 8 hours for anaphylaxis
Doxycycline 10 mg/kg BID for 4 weeks
Exercise restriction (the more pronounced the signs, the stricter the restriction)
If symptomatic:
Stabilize with supportive care
Prednisone 0.5 mg/kg BID first week, 0.5 mg/kg SID second week, 0.5 mg/kg every other day (EOD) for the third and fourth weeks
Day 30:
Apply heartworm preventative
Day 60:
Apply heartworm preventative
Melarsomine 2.5 mg/kg deep IM between L3-L4 (alternating sides)
Pretreat with diphenhydramine 2mg/kg IM and dexamethasone 0.125mg/kg IM
Prednisone 0.5 mg/kg BID first week, 0.5 mg/kg SID second week, 0.5 mg/kg EOD for the third and fourth weeks
Decrease activity even further (cage restriction, on leash when using yard)
Day 90:
Apply heartworm preventative
Melarsomine 2.5 mg/kg deep IM between L3-L4 (alternating sides)
Pretreat with diphenhydramine 2mg/kg IM and dexamethasone 0.125mg/kg IM
Day 91:
Melarsomine 2.5 mg/kg deep IM between L3-L4 (alternating sides)
Pretreat with diphenhydramine 2mg/kg IM and dexamethasone 0.125mg/kg IM
Prednisone 0.5 mg/kg BID first week, 0.5 mg/kg SID second week, 0.5 mg/kg EOD for the third and fourth weeks
Continue exercise restriction for 6 to 8 weeks following last melarsomine injections
Day 120:
Microfilaria Filter Test (1 month after last melarsomine injection)
If positive, treat with a microfilaricide and retest in 4 weeks
Continue heartworm preventatives based on risk assessment
Day 365:
Heartworm Antigen Test (9 months after last melarsomine injection)
If positive, re-treat with doxycycline followed by two doses of melarsomine 24 hours apart