Spectinomycin: veterinary dose and monograph

At a glance

Drug class

Antibiotic

Also known as

Spectam, Linco-Spectin (with lincomycin), Adspec

Species with doses

Dogs, Cats, Cattle, Horses, Pigs and Poultry

General dose range

10–20 mg/kg IM q12–24h — check the species tables for the indication

Routes

IM, SC, PO

Last reviewed

1 October 2026

Indications

• Poultry: colibacillosis, chronic respiratory disease / Mycoplasma (CRD), coryza
• Swine: enteric (E. coli) and respiratory infections, Mycoplasma
• Calf colibacillosis / enteric infection
• Surgical / soft-tissue susceptible infection (small animal, less common)

Spectinomycin dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Dogs

• Susceptible infection: Papich 5e and Plumb’s p.1072 (Kintzer & Peterson): 5.5–11 mg/kg IM q12h for 4 days; acute infectious gastroenteritis 5–12 mg/kg IM q12h (DeNovo).
• Enteric infection (oral, not absorbed): Papich 5e and Plumb’s p.1072: 22 mg/kg PO q12h for enteric infections — not absorbed from the gut.

Cats

• Acute infectious gastroenteritis: Plumb’s p.1072 (DeNovo 1986): 5–12 mg/kg IM q12h.

Cattle

• Bovine respiratory disease (label): Papich 5e and Plumb’s p.1072 (Adspec label): 10–15 mg/kg SC in the neck once daily for 3–5 days, not more than 50 mL per site. US label slaughter withdrawal 11 days; not for veal calves or dairy cattle 20 months or older.

Horses

• Susceptible infection / pneumonia: Plumb’s p.1072: 20 mg/kg IM three times daily (Robinson; Beech) — may cause local myositis; limited data.

Pigs

• Enteric / respiratory infection: Papich 5e: pigs 6.6–22 mg/kg q12–24h IM (or 50–100 mg per pig PO). Plumb’s p.1072: 10 mg/kg IM q12h (Baggot 1983); enteric 10 mg/kg PO q12h. No US injectable label for pigs — obtain a withdrawal (FARAD).

Poultry

• CRD / synovitis (drinking water): Plumb’s p.1072 (Spectam Water-Soluble label): broilers — Mycoplasma gallisepticum CRD 2 g/gallon; M. synoviae synovitis 1 g/gallon. Day-old poults/chicks: injectable 10 mg (0.1 mL) SC per poult, or diluted 2.5–5 mg per chick SC. Follow the product-label withdrawal.

Buffalo

No buffalo-specific doses are on file, so buffalo are dosed as cattle.

• Bovine respiratory disease (label): Papich 5e and Plumb’s p.1072 (Adspec label): 10–15 mg/kg SC in the neck once daily for 3–5 days, not more than 50 mL per site. US label slaughter withdrawal 11 days; not for veal calves or dairy cattle 20 months or older.

Contraindications

Known hypersensitivity. Avoid in adult horses and hindgut fermenters (lincomycin component of combinations causes fatal colitis). Use combinations per species label only. Renal impairment (reduce/space dosing).

Species-specific warnings

Horses: Lincomycin-spectinomycin combinations cause fatal colitis in horses — strictly contraindicated.

Rabbits: Avoid combination products — lincomycin is fatal to rabbits.

Adverse effects

• Generally well tolerated; injection-site reactions
• GI flora disturbance (oral)
• Lincomycin-component colitis in the wrong species (combination products)
• Mild, reversible vestibular signs at very high doses (rare)

Drug interactions

• In combination with lincomycin: complementary (Gram-negative + Gram-positive/Mycoplasma) spectrum — the basis of Linco-Spectin
• Additive risk with other nephro-/ototoxic drugs (low intrinsic risk)
• Antagonism with bactericidal agents (theoretical, bacteriostatic action)

Pregnancy and lactation

Limited data; considered relatively low-risk. Combination products should follow species label restrictions in breeding stock.

Monitoring

• Flock/herd clinical response over 3–5 days
• GI tolerance (especially combination products)
• Withdrawal-period compliance in food animals
• Renal function on prolonged high-dose courses

Toxicity and overdose

Wide margin of safety — markedly less ototoxic/nephrotoxic than aminoglycosides. Overdose is usually limited to GI upset; the lincomycin component of combinations is the real hazard in horses/rabbits (fatal colitis).

Management: Supportive; no specific antidote. Discontinue, fluid support, and manage GI signs. Treat colitis aggressively if a lincomycin-containing product is misused in a susceptible species.

Clinical pearls

• Think "Linco-Spectin" for poultry CRD/coryza and swine enteric-respiratory disease — the combo is the workhorse
• Lower toxicity than aminoglycosides makes spectinomycin handy where renal margin matters
• Never let a lincomycin-spectinomycin product reach horses or rabbits — the lincomycin causes lethal colitis
• Prepare medicated drinking water fresh each day for stability and intake

Mechanism of action

Aminocyclitol that binds the 30S ribosomal subunit and inhibits the translocation step of protein synthesis — usually bacteriostatic. Unlike the aminoglycosides it does not cause significant misreading of mRNA, which underlies its comparatively low toxicity.

Formulations and products

• Injection 100 mg/mL
• Soluble powder (oral, poultry/swine)
• Linco-Spectin soluble powder (lincomycin + spectinomycin)
• Linco-Spectin (Zoetis) — Lincomycin 50 mg + Spectinomycin 100 mg per g (soluble powder), Soluble powder (water)
• Spectinomycin injection (Various (India)) — 100 mg/mL, Injection
• Trobicin (historical) — 2 g vial, Injection (human-label)

Storage

Injection and soluble powders: 15–30 °C, dry, protected from light. Reconstituted/medicated water: prepare fresh daily.

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

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Frequently asked questions