Pentacarinat
pentamidine isethionate
Pharmacologic class: Antiprotozoal
Therapeutic class: Anti-infective
Pregnancy risk category C
Action
Unknown. May interfere with nuclear metabolism and synthesis of DNA, RNA, and proteins.
Availability
Aerosol: 300 mg
Injection: 300 mg/vial
Indications and dosages
➣ Pneumocystis jiroveci pneumonia
Adults and children ages 5 and older: 4 mg/kg I.V. or deep I.M. daily for 14 days
➣ To prevent P. jiroveci pneumonia in high-risk patients with human immunodeficiency virus
Adults: 300 mg by inhalation once q 4 weeks using Respigard II nebulizer
Off-label uses
• Trypanosomiasis
• Visceral leishmaniasis
Contraindications
• History of anaphylaxis from pentamidine or diamidine compounds (inhalation only)
(Note: No absolute contraindications exist for patients with P. jiroveci.)
Precautions
Use cautiously in:
• anemia, blood dyscrasias, hepatic or renal disease, hypoglycemia, diabetes mellitus, ventricular tachycardia, hypocalcemia, hypertension, hypotension
• pregnant or breastfeeding patients
• children (safety and efficacy of inhalation solution not established).
Administration
• For I.V. infusion, dilute 300 mg-vial with sterile water for injection. Withdraw prescribed dosage, then dilute further in 50 to 250 ml of dextrose 5% in water; infuse over 60 to
120 minutes.
• For I.M. use, dilute 300 mg-vial with 3 ml of sterile water for injection. Withdraw prescribed dosage; administer deep I.M. using Z-track method.
• Keep patient supine during I.M. or I.V. administration to minimize hypotension.
• For inhalation, dilute in 6 ml of sterile water and administer through nebulizer at a flow rate of 6 L/minute from 50-psi compressed air source. Don't mix inhalation solution with other drugs.
Adverse reactions
CNS: headache, disorientation, hallucinations, dizziness, confusion, fatigue, neuralgia
CV: chest pain, ECG abnormalities, syncope, vasodilation, vasculitis, phlebitis, hypertension, palpitations, arrhythmias, severe hypotension
EENT: pharyngitis
GI: nausea, vomiting, diarrhea, abdominal pain, anorexia, acute pancreatitis
Hematologic: anemia, leukopenia, thrombocytopenia
Metabolic: hypocalcemia, hypergly-cemia, hypoglycemia, hyperkalemia Musculoskeletal: myalgia
Respiratory: cough, dyspnea, congestion, pneumothorax, bronchospasm
Skin: rash, night sweats, urticaria, sterile abscess or induration at injection site
Other: metallic or bad taste, fever, chills, pain at injection site or elsewhere, edema, allergic reactions
Interactions
Drug-diagnostic tests. Blood urea
nitrogen, creatinine, liver function tests,
potassium: increased values
Calcium, hemoglobin, hematocrit,
platelets, white blood cells: decreased levels
ECG: alterations
Glucose: increased or decreased level
Patient monitoring
See Closely monitor blood pressure and blood glucose. Watch for arrhythmias and evidence of pulmonary infection, blood dyscrasias, and pancreatitis during and after I.M. or I.V. administration, until patient is stable. (Severe, life-threatening reactions may occur.)
• Assess I.V. site closely during and after I.V. administration. Know that sterile abscess, pain, or induration may occur at injection site.
• Evaluate neurologic status.
• Monitor CBC (including platelet count), calcium and potassium levels, and kidney and liver function tests.
Patient teaching
• Explain purpose of therapy. Stress importance of completing entire course of treatment.
See Teach patient to recognize and immediately report serious cardiovascular and neurologic reactions, abdominal pain, and easy bruising or bleeding.
• Teach patient how to use aerosol.
• Tell patient to notify prescriber if infection worsens.
• Advise patient to minimize GI upset by eating small, frequent servings of food and drinking plenty of fluids.
• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the tests mentioned above.