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Pentamidine Isethionate
Overview
Active ingredients
Source: NDC DirectoryForms, strengths and routes
Source: NDC DirectoryPharmacologic classes are listed in the class section below.
Pharmacologic class
Source: NDC Directory| Class | Type | Browse |
|---|---|---|
| Antiprotozoal [EPC] | EPC | All 10 members |
Regulatory status
Source: Drugs@FDANDC Directory| Product | Trade name | Form | Strength | Ingredient | Status | TE | Flags |
|---|---|---|---|---|---|---|---|
| 206666-001 | PENTAMIDINE ISETHIONATE | INJECTABLE | PENTAMIDINE ISETHIONATE | Prescription | AP |
Therapeutic equivalence
Source: Orange BookWhat this rating means: Therapeutically equivalent — bioequivalence demonstrated (parenteral aqueous solutions)
Codes beginning with “A” indicate products the FDA considers therapeutically equivalent. Codes beginning with “B” indicate bioequivalence has not been established. See methodology.
Approval history
Source: Drugs@FDA| Type | No. | Action | Status | Date | Review |
|---|---|---|---|---|---|
| Original application | 1 | Approved | September 28, 2017 | Standard |
Prescribing information
Source: openFDA Drug LabelingReproduced verbatim from the Structured Product Labeling submitted to the FDA (effective 20260507). This is the manufacturer's labelling text, not a summary and not advice.
Indications and Usage
openFDA Drug LabelingINDICATIONS AND USAGE Pentamidine isethionate for injection is indicated for the treatment of pneumonia due to Pneumocystis carinii .
Dosage and Administration
openFDA Drug LabelingDOSAGE AND ADMINISTRATION CAUTION: DO NOT USE SODIUM CHLORIDE INJECTION, USP FOR INITIAL RECONSTITUTION BECAUSE PRECIPITATION WILL OCCUR. Pentamidine isethionate should be administered IM or IV only. The recommended regimen for adults and pediatric patients beyond 4 months of age is 4 mg/kg once a day for 14 to 21 days. Therapy for longer than 21 days with pentamidine isethionate has also been used but may be associated with increased toxicity. Intramuscular Injection The contents of one vial (300 mg) should be dissolved in 3 mL of Sterile Water for Injection, USP at 22° - 30°C (72° - 86°F). The calculated daily dose should then be withdrawn and administered by deep IM injection. Intravenous Injection The contents of one vial (300 mg) should first be dissolved in 3 to 5 mL of Sterile Water for Injection, USP, or 5% Dextrose Injection, USP at 22°- 30°C (72° - 86°F). The calculated dose of pentamidine isethionate should then be withdrawn and diluted further in 50 to 250 mL of 5% Dextrose Injection, USP. The diluted IV solutions containing pentamidine isethionate should be infused over a period of 60 to 120 minutes. Aseptic technique should be employed in preparation of all solutions. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution and container permit. Stability After reconstitution with sterile water, the Pentam solution is stable for 48 hours in the original vial at room temperature if protected from light. To avoid crystallization, store at 22° - 30°C (72° - 86°F). Intravenous infusion solutions of pentamidine isethionate at 1 mg/mL and 2.5 mg/mL prepared in 5% Dextrose Injection, USP are stable at room temperature for up to 24 hours. Intravenous (IV) solutions of pentamidine isethionate have been shown to be incompatible with fluconazole and foscarnet sodium. IV solutions of pentamidine isethionate have been shown to be compatible with IV solutions of zidovudine (AZT) and diltiazem hydrochloride.
Intramuscular Injection The contents of one vial (300 mg) should be dissolved in 3 mL of Sterile Water for Injection, USP at 22° - 30°C (72° - 86°F). The calculated daily dose should then be withdrawn and administered by deep IM injection.
Intravenous Injection The contents of one vial (300 mg) should first be dissolved in 3 to 5 mL of Sterile Water for Injection, USP, or 5% Dextrose Injection, USP at 22°- 30°C (72° - 86°F). The calculated dose of pentamidine isethionate should then be withdrawn and diluted further in 50 to 250 mL of 5% Dextrose Injection, USP. The diluted IV solutions containing pentamidine isethionate should be infused over a period of 60 to 120 minutes. Aseptic technique should be employed in preparation of all solutions. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution and container permit.
Stability After reconstitution with sterile water, the Pentam solution is stable for 48 hours in the original vial at room temperature if protected from light. To avoid crystallization, store at 22° - 30°C (72° - 86°F). Intravenous infusion solutions of pentamidine isethionate at 1 mg/mL and 2.5 mg/mL prepared in 5% Dextrose Injection, USP are stable at room temperature for up to 24 hours. Intravenous (IV) solutions of pentamidine isethionate have been shown to be incompatible with fluconazole and foscarnet sodium. IV solutions of pentamidine isethionate have been shown to be compatible with IV solutions of zidovudine (AZT) and diltiazem hydrochloride.
Contraindications
openFDA Drug LabelingCONTRAINDICATIONS Contraindicated in patients with a history of hypersensitivity to pentamidine isethionate.
Warnings
openFDA Drug LabelingWARNINGS Fatalities due to severe hypotension, hypoglycemia, acute pancreatitis and cardiac arrhythmias have been reported in patients treated with pentamidine isethionate, both by the IM and IV routes. Severe hypotension may result after a single IM or IV dose and is more likely with rapid IV administration (see PRECAUTIONS ). The administration of the drug should, therefore, be limited to the patients in whom Pneumocystis carinii has been demonstrated. Patients should be closely monitored for the development of serious adverse reactions (see PRECAUTIONS and ADVERSE REACTIONS ). Extravasations have been reported which, in some instances, proceeded to ulceration, tissue necrosis and/or sloughing at the injection site. While not common, surgical debridement and skin grafting has been necessary in some of these cases; long-term sequelae have been reported. Prevention is the most effective means of limiting the severity of extravasation. The intravenous needle or catheter must be properly positioned and closely observed throughout the period of pentamidine isethionate administration. If extravasation occurs, the injection should be discontinued immediately and restarted in another vein. Because there are no known local treatment measures which have proven to be useful, management of the extravasation should be symptomatic.
Adverse Reactions
openFDA Drug LabelingADVERSE REACTIONS CAUTION : Fatalities due to severe hypotension, hypoglycemia, acute pancreatitis and cardiac arrhythmias have been reported in patients treated with pentamidine isethionate, both by the IM and IV routes. Nephrotoxic events (increased creatinine, impaired renal function, azotemia, and renal failure) are common with the parenteral administration of pentamidine isethionate. The administration of the drug should, therefore, be limited to the patients in whom Pneumocystis carinii has been demonstrated. The most frequently reported spontaneous adverse events (1 to 30%) reported in clinical trials, regardless of their relation to pentamidine isethionate therapy were as follows (n=424): Cardiovascular: -Hypotension 5.0% Gastrointestinal: -Anorexia/Nausea 5.9% Hematologic: -Anemia 1.2% -Leukopenia 10.4% -Thrombocytopenia 2.6% Hepatic: -Elevated liver function tests 8.7% Metabolic: -Hypoglycemia 5.9% Neurologic: -Confusion/hallucinations 1.7% Skin: -Sterile abscess and/or necrosis, pain, or induration at the site of IM injection 11.1% -Rash 3.3% Special Senses: -Bad taste 1.7% Urogenital: -Azotemia 8.5% -Elevated serum creatinine 23.6% -Elevated blood urea nitrogen 6.6% -Impaired renal function 28.8% Adverse events with a frequency of less than 1% incidence were as follows (No causal relationship to treatment has been established for these adverse events): Body as a whole: Allergic reaction (i.e. urticaria, itching, rash), anaphylaxis, arthralgia, chills, extrapulmonary pneumocystosis, headache, night sweats, and Stevens-Johnson syndrome. Cardiovascular: Abnormal ST segment of electrocardiogram, cardiac arrhythmias, cerebrovascular accident, hypertension, palpitations, phlebitis, syncope, tachycardia, vasodilatation, vasculitis and ventricular tachycardia. Gastrointestinal: Abdominal pain, diarrhea, dry mouth, dyspepsia, hematochezia, hypersalivation, melena, pancreatitis, splenomegaly, and vomiting. Hematological: Defibrination, eosinophilia, neutropenia, pancytopenia, and prolonged clotting time. Hepatic: Hepatic dysfunction, hepatitis and hepatomegaly Metabolic: Hyperglycemia, hyperkalemia, hypocalcemia, and hypomagnesemia. Neurological: Anxiety, confusion, depression, dizziness, drowsiness, emotional lability, hypesthesia, insomnia, memory loss, neuropathy, nervousness, neuralgia, paranoia, paresthesia, peripheral neuropathy, seizure, tremors, unsteady gait, and vertigo. Respiratory system: Asthma, bronchitis, bronchospasm, chest congestion, chest tightness, coryza, cyanosis, eosinophilic or interstitial pneumonitis, gagging, hemoptysis, hyperventilation, laryngitis, laryngospasm, non-specific lung disorder, nasal congestion, pleuritis, pneumothorax, rales, rhinitis, shortness of breath, and tachypnea. Skin: Desquamation, dry and breaking hair, dry skin, erythema, dermatitis, pruritus, rash, and urticaria. Special senses: Blepharitis, blurred vision, conjunctivitis, contact lens discomfort, eye pain or discomfort, loss of hearing, loss of taste, and loss of smell. Urogenital: Flank pain, hematuria, incontinence, nephritis, renal dysfunction and renal failure. From post-marketing clinical experience with pentamidine isethionate, the following adverse events have been reported: cough, diabetes mellitus/ketoacidosis, dyspnea, infiltration (extravasation–see WARNINGS ), and torsades de pointes. To report SUSPECTED ADVERSE REACTIONS, contact XGen Pharmaceuticals DJB, Inc. at 1-866-390-4411 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
Drug Interactions
openFDA Drug LabelingDrug Interactions No drug interaction studies with pentamidine isethionate for injection have been conducted. Because the nephrotoxic effects may be additive, the concomitant or sequential use of pentamidine isethionate and other nephrotoxic drugs such as aminoglycosides, amphotericin B, cisplatin, foscarnet, or vancomycin should be closely monitored and avoided, if possible.
Description
openFDA Drug LabelingDESCRIPTION Pentamidine isethionate for injection, an anti-protozoal agent, is a sterile, nonpyrogenic, lyophilized product. After reconstitution, it should be administered by intramuscular (IM) or intravenous (IV) routes (see DOSAGE AND ADMINISTRATION ). Pentamidine isethionate is a white crystalline powder soluble in water and glycerin, slightly soluble in alcohol and insoluble in ether, acetone, and chloroform. It is chemically designated as 4,4'-(Pentane-1,5-diylbis(oxy)) dibenzimidamide bis(2-hydroxyethanesulfonate) with the following structural formula: Molecular Formula: C 19 H 24 N 4 O 2 . (C 2 H 6 O 4 S) 2 Molecular Weight: 592.68 Each vial contains: Pentamidine isethionate USP . . . . . . . . . . . . . 300 mg structural-formula
Overdosage
openFDA Drug LabelingOVERDOSAGE A 17 month old infant inadvertently received 1,600 mg of intravenous pentamidine isethionate which was followed by renal and hepatic function impairment, hypotension and cardiopulmonary arrest. Treatment included cardiopulmonary resuscitation, epinephrine, atropine and intubation. In addition, a four hour course of charcoal hemoperfusion was accompanied by reduction of pentamidine serum concentration and stabilization of the patient's condition. The patient recovered from these adverse events, but later died due to an unknown cause. 1
How Supplied / Storage and Handling
openFDA Drug LabelingHOW SUPPLIED NDC No. 0121-1101-02 Pentamidine Isethionate for Injection 300 mg, lyophilized product in single dose vials (NDC 0121-1101-55), 10 vials per carton. Store dry product at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature]. Protect from light. Preservative Free. Discard unused portion. To report SUSPECTED ADVERSE REACTIONS, contact PAI Pharma at 1-800-845-8210 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
Adverse event reports
Source: openFDA FAERSAttributed to this product's most-reported active ingredient: PENTAMIDINE ISETHIONATE. Combination products with more than six active ingredients are not attributed, because a report count summed across a long ingredient list measures the list, not the medicine.
Packaging and NDCs
Source: NDC Directory| Package NDC | Product NDC | Labeler | Description | Marketing start |
|---|---|---|---|---|
| 23155-748-41 | 23155-748 | Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc. | 10 VIAL, SINGLE-DOSE in 1 CARTON (23155-748-41) / 300 mg in 1 VIAL, SINGLE-DOSE (23155-748-31) | January 8, 2021 |
| 0121-1101-02 | 0121-1101 | PAI Holdings, LLC dba PAI Pharma | 10 VIAL, SINGLE-USE in 1 CARTON (0121-1101-02) / 300 mg in 1 VIAL, SINGLE-USE (0121-1101-55) | June 12, 2026 |
| 13925-515-10 | 13925-515 | Seton Pharmaceuticals | 10 VIAL in 1 TRAY (13925-515-10) / 300 mg in 1 VIAL | April 1, 2018 |
| 39822-3050-2 | 39822-3050 | XGen Pharmaceuticals DJB, Inc. | 10 VIAL in 1 CARTON (39822-3050-2) / 3 mL in 1 VIAL | April 4, 2023 |
| 23155-748 | 23155-748 | Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc. | — | January 8, 2021 |
| 0121-1101 | 0121-1101 | PAI Holdings, LLC dba PAI Pharma | — | June 12, 2026 |
| 13925-515 | 13925-515 | Seton Pharmaceuticals | — | April 1, 2018 |
| 39822-3050 | 39822-3050 | XGen Pharmaceuticals DJB, Inc. | — | April 4, 2023 |
Sources for this page
| Dataset | Agency | Used for |
|---|---|---|
| NDC Directory | FDA | Identity, ingredients, strengths, forms, routes, labelers, packages |
| Drugs@FDA | FDA | Application, sponsor, submissions, review documents, marketing status |
| Orange Book | FDA | Therapeutic equivalence codes, reference drug flags, patents, exclusivity |
| Drug Labeling | FDA / NLM | Prescribing information reproduced above |
| FAERS | FDA | Adverse event report counts |
Generated September 25, 2026 · 12 sections on this page.