skip to Main Content




Solution for parenteral administration


Metamizole is a pyrazolone non-steroidal anti-inflammatory drug (NSAID) with analgesic and antipyretic properties. Its mode of action is similar to that of other NSAIDs and involves the inhibition of prostaglandin synthesis via cyclooxygenase. In contrast to other NSAIDs, metamizole also has antispasmodic activity. After intramuscular injection metamizole is rapidly absorbed, reaching maximum blood levels after 1 to 2 hours. Metamizole and its metabolites are predominantly excreted in urine (85%) and to a lesser degree (15%) in faeces. A clinical effect is typically observed within 30 minutes after intramuscular injection.


Castralgin is indicated for relief of pain associated with various forms of colic of various etiologies and other spastic conditions of the abdominal organs, for acute and chronic arthritis, serositis, rheumatic conditions of muscles and joints, neuritis, neuralgia, tendovaginitis and other diseases involving high fever and/or inflammation processes in calves, cattle, swine and dogs.

Contra indications

Hypersensitivity to the active ingredient.
Administration to animals with seriously impaired renal and/or hepatic functions.
Concurrent administration of barbiturates, phenylbutazone or other NSAIDs.
Administration to animals producing milk for human consumption.

Side effects

Gastrointestinal disorders (nausea, vomiting diarrhoea), gastric ulcers.
Risk of bleedings, blood dyscrasias. Renal papillary necrosis.
Long-term use of Castralgin may lead to leucopenia and/or agranulocytosis.


For intramuscular administration.

Once 40 mg per kg body weight (corresponding to 8 ml of Castalgin per 100 kg of body weight).

Once 40 – 50 mg per kg body weight (corresponding to 8 – 10 ml per 100 kg body weight).

Once 75 – 100 mg per kg body weight (corresponding to 15 – 20 ml per 100 kg body weight).

70 – 100 mg per kg body weight (corresponding to 1.4 – 2 ml per 10 kg body weight). The dose may be repeated if necessary. Note: Castralgin can be used safely during gestation and lactation, provided the milk is not destined for human consumption.

Withdrawal times

– For meat:
Cattle : 20 days.
Calf : 28 days.
Swine : 17 days.


Vial of 100 ml.
Back To Top
Need Help? Chat with us