nafcillin sodium

naf·cil·lin sodium (nfsln)

n.

An intravenous antibiotic used to treat staphylococcal infections.

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nafcillin sodium

[nafsil′in]

an antibiotic.

indications It is prescribed in the treatment of infections caused by penicillinase-producing staphylococci.

contraindications Known hypersensitivity to this drug or to other penicillins prohibits its use.

adverse effects Among the more serious adverse effects are hypersensitivity reactions, nausea, and vomiting.

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nafcillin sodium

Pharmacologic class: Penicillinase-resistant penicillin

Therapeutic class: Anti-infective

Pregnancy risk category B

Action

Inhibits cell-wall synthesis during microorganism multiplication; resists inactivation by staphylococcal penicillinase. Bactericidal.

Availability

I.V. infusion (piggyback): 1 g, 2 g

⊘Indications and dosages

➣ Systemic infections caused by penicillinase-producing staphylococci

Adults: 500 mg I.V. q 4 hours; for more severe infections, 1 g I.V. q 4 hours. Duration depends on type and severity of infection.

Dosage adjustment

• Children

Contraindications

• Hypersensitivity to drug or other penicillins

Precautions

Use cautiously in:
• cephalosporin hypersensitivity
• renal disorders, GI distress
• pregnant or breastfeeding patients
• children.

Administration

• Ask patient about penicillin allergy before giving.
• Reconstitute with normal saline solution, dextrose 5% in water (D₅W), dextrose 10% in water, half D₅W/normal saline solution, or half D₅W/lactated Ringer's solution. Administer over 30 to 60 minutes. Don't mix with other drugs in same solution.

Route	Onset	Peak	Duration
I.V.	Immediate	15 min	4 hr

Adverse reactions

CNS: lethargy, hallucinations, anxiety, depression, twitching, coma, seizures

CV: thrombophlebitis

GI: nausea, vomiting, diarrhea

Hematologic: anemia, bone marrow depression, granulocytopenia

Skin: angioedema

Other: superinfection, vein irritation, hypersensitivity reactions including serum sickness and anaphylaxis

Interactions

Drug-drug. Aminoglycosides: synergistic effects

Cyclosporine: subtherapeutic cyclosporine blood level

Hormonal contraceptives: decreased contraceptive efficacy

Probenecid: increased nafcillin blood level

Rifampin: antagonism (dose-dependent)

Warfarin: increased risk of bleeding

Drug-diagnostic tests. Granulocytes, neutrophils, platelets: decreased counts

Drug-herbs. Khat: delayed and reduced nafcillin absorption

Patient monitoring

☞ Assess for signs and symptoms of hypersensitivity reaction (including anaphylaxis, serum sickness, and angioedema), which may occur several days after therapy begins.
☞ Monitor neurologic status. Stay alert for seizures, depression, and hallucinations.
• Evaluate CBC with white cell differential.
• In prolonged therapy, assess for superinfection.

Patient teaching

• Instruct patient to complete entire course of therapy even if symptoms disappear.
☞ Teach patient to recognize and immediately report signs and symptoms of hypersensitivity reactions (including serum sickness and angioedema) as well as bleeding and easy bruising.
• Teach patient about signs and symptoms of superinfection. Instruct him to report these promptly.
• Caution patient to avoid driving and other hazardous activities until he knows how drug affects alertness and motor function.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and herbs mentioned above.