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Nafcillin Inj
Bacterial infections
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Drug Name:

Nafcillin Inj Rx

Generic Name and Formulations:
Nafcillin sodium 1g/vial, 2g/vial, 10g/vial; pwd for deep IM inj after reconstitution, IV inj or IV drip after reconstitution and dilution.

Various generic manufacturers

Therapeutic Use:

Indications for Nafcillin Inj:

Susceptible infections due to penicillinase-producing staphylococci.


Give by deep IM gluteal inj, or IV inj over 5–10 mins, or short-term IV drip for 24–48 hours. IM: 500mg every 4–6 hours. IV: 500mg every 4 hours. Severe infections: 1g IM or IV every 4 hours; treat for at least 14 days, then continue for at least 48 hours after becoming afebrile, asymptomatic, or (–) cultures. Endocarditis or osteomyelitis: may need longer therapy; see literature. Switch to oral therapy as soon as clinically indicated.


Give by deep IM gluteal inj only. Neonates: 10mg/kg twice daily. Infants and children <40kg: 25mg/kg twice daily.


Cephalosporin or other allergy: not recommended. Asthma. Renal impairment: consider dose reduction. Do CBCs, BUN, urinalysis, creatinine levels prior to and weekly during therapy. Monitor renal, hepatic and hematopoietic function in prolonged use. Elderly (esp. IV route). Newborns (monitor). Pregnancy (Cat.B). Nursing mothers.


May be antagonized by tetracycline; avoid. Potentiated by probenecid.

Pharmacological Class:

Penicillinase-resistant penicillin.

Adverse Reactions:

Inj site reactions, rash, serum sickness, GI upset, anaphylaxis, neuropathy, nephropathy, blood dyscrasias.


Formerly known under the brand names Nallpen, Unipen.

How Supplied:

Contact supplier.

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