Gamithromycin is an antibiotic used for the treatment and control of these bacterial pathogens in cattle, pigs, and sheep :

• Mannheimia haemolytica
• Pasteurella multocida
• Histophilus somni
• Mycoplasma bovis (for cattle in the US)
• Actinobacillus pleuropneumoniae (for pigs)
• Bordetella bronchiseptica (for pigs)
• Dichelobacter nodosus and Fusobacterium necrophorum (for sheep foot rot) 

INDICATIONS

• Cattle (Beef and non-lactating dairy cattle only):
  • Treatment of Bovine Respiratory Disease (BRD), also known as “shipping fever,” associated with specific bacteria.
  • Control/Metaphylaxis (prevention) of BRD in cattle at high risk of developing the disease.
• Pigs: Treatment of Swine Respiratory Disease (SRD).
• Sheep: Treatment of infectious pododermatitis (foot rot).

• Administration: It is administered as a single subcutaneous injection in the neck of cattle and sheep, and as a single intramuscular injection in pigs, at a dosage of 6 mg/kg of body weight. The dose should be divided among multiple injection sites if the total volume exceeds 10 mL for cattle or 5 mL for pigs/sheep to avoid tissue reactions.
• Mechanism of Action: Gamithromycin works by inhibiting bacterial protein synthesis, which is primarily a bacteriostatic effect, though it can be bactericidal at higher concentrations achieved in lung tissue.
• Rapid and Long-Lasting: The drug is rapidly absorbed and reaches high concentrations in lung tissue within a short period, and it has a prolonged post-antibiotic effect and a long half-life, meaning a single dose can provide therapy for up to 10 days.