General Drug Information and Indications

Vitamin B1 supplementation for deficiency; polioencephalomalacia in horses and ruminants; adjunct in neurological disease. Vitamin B1 (thiamine HCl). Mechanism: phosphorylated to thiamine pyrophosphate (TPP) → essential coenzyme for pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, and transketolase → central to glucose catabolism and energy metabolism. Deficiency causes polioencephalomalacia (PEM) in ruminants and horses (impaired glucose metabolism in CNS). IV thiamine can be directly neuroprotective. Key information Vitamin B1 injectable. Store at room temperature; protect from light. Critical for neurological function in horses with polioencephalomalacia. IV or IM. May cause anaphylaxis with rapid IV — give slowly.

How to Give this Medication

IV: dilute in compatible IV fluid; administer slowly over 5–10 min (anaphylaxis risk with rapid injection). IM: inject deep IM. PEM treatment (ruminants): administer IV q6–8h acutely. Oral: Administer with food to reduce GI adverse effects. Store at room temperature; protect from light. If a dose is missed Administer as soon as you remember. If it is almost time for the next scheduled dose, skip the missed dose and resume the normal schedule. Never double up doses to make up for a missed one. Thiamine is critical for horses with neurological signs — do not miss doses.

Side Effects

IV rapid injection: anaphylaxis/hypersensitivity reactions (uncommon but documented — give slowly). IM: mild injection site reactions. Generally very safe. High doses: GI upset (uncommon).

Precautions

For animals IV: administer slowly (anaphylaxis risk). Essential for Polioencephalomalacia (PEM) treatment in ruminants — administer immediately when PEM suspected; do not delay for diagnostic confirmation. High doses may be needed; repeat every 6 hrs acutely. For people handling this medication Wash hands thoroughly with soap and water after handling. Avoid contact with eyes; if contact occurs, flush with water for 15 minutes and seek medical attention. Keep out of reach of children. If accidental ingestion occurs, contact Poison Control (1-800-222-1222). Vitamin B1 — generally safe. Wash hands thoroughly with soap and water after handling. Rare anaphylaxis with IV (administered by veterinary staff).

Overdose

Contact your veterinarian. Thiamine overdose causes mild GI signs and rare anaphylaxis with rapid IV injection. Systemic toxicity is low.

Thiamine Hci dosage forms

ProductStrengthFormSizeType
THIAMINE HCI 500 MG/ML INJECTABLE500 MG/MLInjectable1Commercial

Sources

This information is provided for educational purposes and is not a substitute for advice from your veterinarian. Source: Merck Veterinary Manual (merckvetmanual.com); Plumb's Veterinary Drug Handbook (Plumb, D.C., app.plumbs.com)