Antibiotics · Prescription (Rx)
LA-200 (oxytetracycline) withdrawal time for cattle
oxytetracycline 200 & 300 mg/mL — Liquamycin LA-200, Bio-Mycin 200, Noromycin 300 LA, Agrimycin 200, generics. Used for broad-spectrum: pinkeye, foot rot, pneumonia, scours, wounds — the classic multi-purpose cattle antibiotic.
Slaughter withdrawal
28 days
| Route / formulation | Slaughter withdrawal | Detail |
|---|---|---|
| IM, SQ, or IV per product label | 28 days | Applies to both 200 and 300 mg/mL long-acting products |
Milk & dairy: Milk from treated dairy cattle must be withheld 96 hours after the last treatment (where the product is approved for lactating use); several 300 mg/mL products are not for lactating dairy at all — check your bottle.
Long-acting oxytetracycline — LA-200, Bio-Mycin 200, Noromycin 300 LA, and a shelf of generics — is the old reliable of cattle antibiotics: pinkeye, foot rot, pneumonia, and more, at a price that kept it in every ranch fridge. All the common long-acting injectables carry a 28-day slaughter withdrawal.
Two things trip people up. First, since June 2023 it is prescription-only, like every medically important livestock antibiotic — the farm-store OTC era is over. Second, the label’s injection-site limit (10 mL per site in adult cattle) is a residue rule, not just a comfort rule: overloading one site can leave residues past the 28 days.
What the label requires
- Slaughter withdrawal: 28 days for the common 200 and 300 mg/mL long-acting injectables.
- Milk withhold 96 hours where lactating use is on the label; many 300 mg/mL products exclude lactating dairy entirely.
- Max 10 mL per injection site in adult cattle — exceeding it can extend residues beyond the label withdrawal.
- Prescription-only since June 2023 (OTC-to-Rx transition).
Always follow the label on your bottle and your veterinarian's directions. Extra-label use — any different dose, route, or frequency — voids the withdrawal above; your vet sets the interval instead, usually via FARAD. When in doubt, hold longer. Label data checked July 18, 2026. Source: Liquamycin LA-200 FDA label (DailyMed).
Never ship a treated animal by mistake
Log a treatment in HerdCommand with its withdrawal days and the animal carries a hold flag until the date clears — and the sale workflow warns you before a flagged animal ends up on a load. Works from the phone in your pocket, at the chute.
Start a free 14-day trial$19/month flat. No credit card to start.
Common questions
Is the withdrawal different for LA-200 versus LA-300 products?
No — the current U.S. labels for the common 200 mg/mL (LA-200, Bio-Mycin 200) and 300 mg/mL (Noromycin 300 LA) long-acting injectables all specify 28 days to slaughter. What differs is dairy use: check whether your specific product allows lactating cattle.
Why can’t I buy LA-200 over the counter anymore?
In June 2023 FDA moved all remaining medically important livestock antibiotics from OTC to prescription status. The product is unchanged; you now need a veterinarian-client relationship to get it.