Pronunciation: pen-TAM-ih-deen ice-uh-THIGH-uh-nate
- Aerosol 300 mg
- Injection 300 mg
- Injection 300 mg
Mechanism of action not fully understood. Interferes with synthesis of DNA, RNA, phospholipids, and proteins.
Well absorbed after IM administration and detectable in the blood briefly because of extensive tissue binding.
C max is 612 ng/mL (single 2-h IV infusion).
T max is 0.5 to 1 h (IM), 1 to 2 h (IV).
Rapidly distributed with highest concentrations in liver, kidneys, adrenal glands, and spleen; smaller amount in lungs, and slow uptake into CNS and brain tissue.
Vd is 3 to 32 L/kg (at steady state).
Unknown in humans.
Urine (12% as unchanged).
T ½ is 6.4 h (IV), 9.1 to 13.2 h (IM).
Cl is 248 L/h (IV).
Terminal t ½ is 2 to 4 wk.
Special PopulationsRenal Function Impairment
Pentamidine may accumulate in renal failure.
Indications and UsageParenteral form
Treatment of Pneumocystis carinii pneumonia (PCP).Inhalation
Prevention of PCP in high-risk HIV-infected patients.
Treatment of trypanosomiasis and visceral leishmaniasis.
Once diagnosis of PCP is made, there are no absolute contraindications.Inhalation
History of anaphylactic reaction to pentamidine.
Dosage and AdministrationAdults and Children
IM / IV 4 mg/kg every day for 14 days.Adults
Inhalation 300 mg once every 4 wk administered via Respirgard II nebulizer.
- Dissolve contents of vial in sterile water for injection or D5W as directed.
- For IV infusion, solution may be diluted further in D5W.
- Infuse pentamidine IV over 1 h with patient supine to minimize severe hypotension and arrhythmias.
- For IM administration, inject deeply and rotate sites.
- Reconstitute medication for inhalation in sterile water for injection. Do not mix with any other drugs.
- Deliver aerosol dose until nebulizer chamber is empty (approximately 30 to 45 min).
- Reconstituted aerosol preparation is stable up to 48 h at room temperature, if protected from light source. Discard unused portion.
- IV solutions prepared with D5W are stable at room temperature for up to 48 h. Discard unused portion.
- Store unopened vial at controlled room temperature (59° to 86°F). Protect from light.
Do not reconstitute with saline solutions. Do not mix with other drugs.
Laboratory Test Interactions
None well documented.
Hypotension; ventricular tachycardia; cardiac arrhythmias; chest pain; edema; phlebitis.
Confusion; hallucinations; dizziness; fatigue; headache.
Stevens-Johnson syndrome; sterile abscess, pain or induration at IM injection site; rash.
Bad or metallic taste.
Nausea; anorexia; vomiting; diarrhea; abdominal pain.
Acute renal failure; elevated serum creatinine.
Leukopenia; thrombocytopenia; anemia; pancytopenia.
Elevated LFT results.
Hypoglycemia; hypocalcemia; hyperkalemia.
Shortness of breath; cough; pharyngitis; chest congestion; bronchospasm; pneumothorax (generally associated with inhalation).
Neuralgia; myalgia; night sweats, chills.
Category C .
Safety and efficacy of inhalation solution not established.
Reduction of dosage, longer infusion time, or extension of dosing interval may be required.
Special Risk Patients
Use drug with caution in patients with hypertension, hypotension, hypoglycemia, hyperglycemia, hypocalcemia, leukopenia, thrombocytopenia, anemia, hepatic or renal function impairment, ventricular tachycardia, pancreatitis, Stevens-Johnson syndrome.
Development of acute PCP
Acute PCP may develop despite pentamidine prophylaxis.
Fatalities from severe hypotension (even after one dose), hypoglycemia and cardiac arrhythmias have been reported with IM and IV routes. Monitor BP continuously throughout infusion, every 30 min for 2 h thereafter and then every 4 h until BP stabilizes.
- Inform the patient that there may be pain at the injection site with IM administration.
- Caution patient to avoid crowds and persons with known infections.
- Instruct patient to report the following symptoms to health care provider: nausea, vomiting, anorexia, diarrhea, oliguria, dizziness, chest pain, or edema.
- Advise patient that drug may cause dizziness, and to use caution while driving or performing other tasks requiring mental alertness.
Copyright © 2009 Wolters Kluwer Health.