Silgram

Description

FORMULATION

Each tablet contains 750 mg of Sultamicillin (as tosylate)

Description

Sultamicillin tosylate is a prodrug of ampicillin and of the beta-lactamase inhibitor sulbactam. It consists of the two compounds linked as a double ester. During absorption from the gastrointestinal tract it is hydrolysed, releasing equimolar quantities of ampicillin and sulbactam.

CLINICAL PHARMACOLOGY

Mechanism of Action

Sultamicillin tosylate inhibits beta-lactamases in penicillin-resistant microorganisms and it acts against sensitive organisms during the stage of active multiplication by inhibiting biosynthesis of cell wall mucopeptide.

PHARMACOKINETICS

Bioavailability of an oral dose is 80% of an equal IV dose of sulbactam and ampicillin. Sultamicillin undergoes hydrolysis during absorption to provide sulbactam and ampicillin 1:1 molar ratio following oral administration. Peak serum levels of ampicillin following sultamicillin are approximately twice those of an equal dose of oral ampicillin. Elimination half-life is approximately 0.75 and 1 hour for sulbactam and ampicillin respectively with 50-75% of each agent being excreted in the urine unchanged while in elderly patients with renal dysfunction, elimination half-life is increased.

INDICATIONS

Sultamicillin tosylate is used in the treatment of gonococcal infections, otitis media, pyelonephritis, upper and lower respiratory tract infections, urinary tract infections, and skin and soft tissue infections.

DOSAGE AND ADMINISTRATION

For adults:

Usual dose: 375 mg to 750 mg twice daily.

For uncomplicated gonorrhoea: 2.25 g with probenecid 1 g.

CONTRAINDICATIONS

Hypersensitivity to penicillins.

PRECAUTIONS

• Overgrowth of nonsusceptible organisms and superinfections
• Hepatic, renal and hemapoietic dysfunction
• Patients with mononucleosis
• Neonates and other infants
• Pregnancy and lactation

ADVERSE EFFECTS

• Anaphylactic shock
• Diarrhea or loose bowel, nausea, vomiting, epigastric distress and abdominal cramps
• Anemia, thrombocytopenia, eosinophilia and leucopenia
• Transient elevations of ALT (SGPT) and AST (SGOT) transaminases, bilirubinemia, abnormal hepatic function and jaundice
• Rash, itching and other skin reactions

DRUG INTERACTIONS

Concurrent use with warfarin and methotrexate increases risk of bleeding due to toxicity; efficacy of estrogen-containing oral contraceptives is decreased upon concurrent use; excretion ampicillin is reduced when used with probenecid.

STORAGE

Store at temperatures not exceeding 30°C.

REFERENCES

1. Martindale 35th edition
2. Friedel HA, et al. Sultamicillin: a review of its antibacterial activity, pharmacokinetic properties and therapeutic use. Drugs 1989; 37: 491-522.