Erythromycin: what the FDA reviewed for dog products
1 Freedom of Information summary from the FDA Center for Veterinary Medicine for products containing Erythromycin, as typed records: every value below is followed by the verbatim passage it was taken from. Species as stated by each summary: Cattle (bovine).
Products
- Gallimycin® Injection Gallimycin®-100 (NADA/ANADA 012-123)
Gallimycin® Injection Gallimycin®-100 NADA 012-123, Supplemental approval, June 30, 1993; sponsor Bimeda Animal Health Ltd.; species: Cattle (bovine); foi_id 1282; FDA PDF
Indication
Treatment of bovine respiratory disease (shipping fever complex and bacterial pneumonia) associated with Pasteurella multocida susceptible to erythromycin
Dose regimen
4 mg per pound body weight, Intramuscular injection only, Daily, Up to 5 days; cattle should not be slaughtered within 21 days of last injection (6-day residue withdrawal, extended to avoid excessive trim)
bioavailability and comparability data submitted adequately demonstrated that sufficient drug levels were maintained at a dosage of 4 mg per pound body weight administered daily for up to 5 days.
Pharmacokinetics
| Parameter | Value | Conditions | Quote |
|---|---|---|---|
| half-life | 30-hour (conservative estimate) | Cattle; erythromycin residue depletion at the IM injection site after 4 mg/lb daily for 5 days, used to compute the withdrawal period (a residue depletion figure, not a plasma PK value) | However, using a conservative 30-hour half-life, residue at the injection site will deplete to a consumption adjusted tolerance of 1.0 ppm within 6 days. |
Target-animal safety
dose multiples 1X (4 mg/lb); duration Up to five consecutive daily IM injections; animals 24 (two injections 14 days apart), five (three daily injections), 18 (five daily injections).
During these three studies, 24 animals were given two separate injections 14 days apart, five animals were given three consecutive daily injections and 18 animals were given five consecutive daily injections.
| Finding | Quote |
|---|---|
| Transient injection-site swelling for a few days; no externally observable hemorrhage, fibrosis or necrosis | The injections were given intramuscularly in the leg or neck at a dose of 4 mg/lb. body weight. Transient reactions such as injection site swelling were observed over a few days following these injections, but no evidence of hemorrhage, fibrosis, or necrosis was externally observable. |
| Injection-site lesions in 18 cattle (6.5-8.8 mL/site, 5 daily injections) averaged about 1.25 cm diameter x 2.9 cm deep | Gross inspection revealed that injection site lesions were variable in size with approximate average dimensions of 1.25 cm diameter X 2.9 cm deep. |
| Histopathology: central core of acutely necrotic muscle fibers surrounded by degenerating fibers with sarcoplasmic mineralization | Histopathological examination revealed a central core of acutely necrotic muscle fibers. |
| Livers and kidneys grossly and histologically unremarkable | Livers and kidneys were examined grossly and histopathologically with no unusual or unexpected observations reported. |
Effectiveness
No new clinical study in this supplement; effectiveness rests on the NAS/NRC DESI review and FDA's 1976 finding, supported by bioavailability and comparability data at 4 mg/lb daily for up to 5 days; result: FDA concluded the data supported effectiveness for treatment of bovine respiratory disease only; all other disease claims and several species were deleted from the labeling
the agency stated that it had concluded that data supported effectiveness for the/ treatment of bovine respiratory disease only
Adverse reactions
| Term | Treated | Control | Quote |
|---|---|---|---|
| Adverse effects (bioequivalency, milk residue and tissue residue studies) | Safety of this product is also substantiated by the absence of any adverse effects reported in three new studies: a bioequivalency study, and the treatment periods of a milk residue study and a tissue residue study. |
Extraction notes: Supplemental NADA (1993; DESI finalization plus change of tissue tolerance from zero to 0.1 ppm) for a CATTLE product; it appears in the dog set only because the 1970 DESI evaluation covered dogs among other species, and dogs were deleted from the indications. species_class is recorded as cattle because the summary has no Species/Class field and the indication and all studies are bovine; the record must not be treated as canine data. The 'effectiveness' entry is a regulatory (DESI) finding, not a study; n_dogs is not applicable. TAS is the injection-site tolerance observation set at the 1X dose, not a dose-multiple margin study. Sponsor: Sanofi Animal Health.
Reproduce: foi_structured_search(query="Erythromycin") and foi_summary_get(foi_id=...) in dog-geroscience-mcp; dataset foi-summaries-dog (config structured).