Ampicillin Sodium is indicated for the treatment of infections caused by susceptible organisms, including:

• Genitourinary tract infections (including gonorrhea): E. coli, Proteus mirabilis, enterococci, Shigella, Salmonella (including S. typhi), and non-penicillinase producing Neisseria gonorrhoeae
• Respiratory tract infections: Non-penicillinase producing Haemophilus influenzae, staphylococci, and streptococci including Streptococcus pneumoniae
• Gastrointestinal tract infections: Shigella, Salmonella, E. coli, Proteus mirabilis, and enterococci
• Meningitis: Caused by Neisseria meningitidis

Bacteriological testing and sensitivity studies should be performed to identify the causative organism. However, treatment may be initiated before the test results are available.

Ampicillin acts by inhibiting bacterial cell wall synthesis. It binds to penicillin-binding proteins (PBPs), blocking the final stage of peptidoglycan formation in the bacterial cell wall. This leads to weakening of the cell wall and eventual bacterial cell lysis due to the action of autolytic enzymes.

Intra-articular:
Supplement in systemic therapy for treatment of susceptible infections

• Adult: 500 mg daily.
• Child: <10 yr Half of adult routine dosage.

Intraperitoneal:
Supplement in systemic therapy for treatment of susceptible infections

• Adult: 500 mg daily.
• Child: <10 yr Half of adult routine dosage.

Intrapleural:
Supplement in systemic therapy for treatment of susceptible infections

• Adult: 500 mg daily.
• Child: <10 yr Half of adult routine dosage

Intravenous:
Meningitis

• Adult: 2 gm 6 hrly.
• Child: 150 mg/kg daily in divided doses.

Intrapartum prophylaxis against group B Streptoccocal infection in neonates

• Adult: Initially, 2 gm via IV inj followed by 1 gm 4 hrly until delivery.

Oral:
Biliary tract infections, Bronchitis, Endocarditis, Gastroenteritis, Listeriosis, Otitis media, Perinatal streptococcal infections, Peritonitis

• Adult: 0.25-1 gm 6 hrly.
• Child: <10 yr Half of adult routine dosage.

Typhoid and paratyphoid fever

• Adult: 1-2 gm 6 hrly for 2 wk in acute infections, and 4-12 wk in carriers.

Uncomplicated gonorrhoea

• Adult: 2 gm with 1 gm of probenecid as single dose, recommended to be repeated in female patients.

Urinary tract infections

• Adult: 500 mg 8 hrly.

Parenteral:
Susceptible infections

• Adult: 500 mg 6 hrly, via IM or slow IV inj over 3-5 min or by infusion.
• Child: <10 yr Half of adult routine dosage.

Septicaemia

• Adult: 150-200 mg/kg daily. Initiate with IV admin for at least 3 days, then continue with IM inj 3-4 hrly. Continue treatment for at least 48-72 hr after the patient has become asymptomatic or when there is evidence of bacterial eradication. Recommended treatment duration for infections caused by group-A β-haemolytic streptococci: At least 10-days, to prevent occurrence of acute rheumatic fever or acute glomerulonephritis.
• Child: Same as adult dose.

Administration

Should be taken on an empty stomach. Take 1 hr before or 2 hr after meals.

Ampicillin Sodium may decrease the effectiveness of oral contraceptives and oral typhoid vaccines. It can alter INR levels when used with anticoagulants such as warfarin and phenindione. Ampicillin may reduce the elimination of methotrexate, increasing toxicity risk. Drugs like probenecid and sulfinpyrazone reduce its excretion, leading to higher plasma levels. Allopurinol may increase the risk of skin reactions. Absorption may be reduced when taken with chloroquine. Bacteriostatic antibiotics (e.g., erythromycin, chloramphenicol, tetracycline) may interfere with its bactericidal activity.

Contraindicated in patients with known hypersensitivity to ampicillin or other penicillin antibiotics.

Common side effects include nausea, vomiting, diarrhea, and skin rashes. Other reactions may include mouth soreness, black or hairy tongue, erythema multiforme, Stevens–Johnson syndrome, toxic epidermal necrolysis, angioedema, fever, joint pain, and serum sickness-like reactions. Hematological effects such as hemolytic anemia, thrombocytopenia, leukopenia, and neutropenia may occur. Coagulation disorders, prolonged bleeding time, CNS effects (e.g., convulsions, paresthesia), kidney disorders, interstitial nephritis, hepatitis, cholestatic jaundice, elevated liver enzymes, anaphylaxis, and Clostridium difficile-associated diarrhea (CDAD) have also been reported.

Pregnancy Category B. Animal studies have not shown fetal risk, but adequate studies in pregnant women are lacking. Use during pregnancy only if clearly needed.

Use cautiously in patients with a history of beta-lactam allergy. Special care is required in patients with renal impairment and during pregnancy or lactation.

Renal impairment: Dose reduction or extended dosing interval is required when creatinine clearance is below 10 mL/min.

Symptoms may include nausea, vomiting, and diarrhea. Management involves symptomatic and supportive treatment. The drug can be removed by haemodialysis.

Store at 20–25°C. Reconstituted oral suspension should be stored at 2–8°C and discarded after 14 days.