FDA-filed SPL labeling · retrieved through openFDA

Pentamidine Oral Inhalation

Pentamidine isethionate is an antiprotozoal medication used to prevent and treat Pneumocystis jiroveci pneumonia (PJP) in HIV-infected patients, available as an inhaled formulation and as an injection.

Brand names NebuPentPentamPentamidine IsethionatePentam 300
Drug class Antiprotozoal
Rx Forms 2 Routes Respiratory (inhalation) · Intramuscular; Intravenous · Intramuscular, Intravenous
Dr. Brian Staiger, PharmD, BCPS
Reviewed by Last reviewed Jul 10, 2026
🧬 Where this information comes from Click to expand

The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 9 clinical label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →

At a glance
Linked label effectiveSep 13, 2022
Clinical labels in scope 9
AvailabilityRx
Earliest approval/marketing year 1984
FDA-listed product records 23
Boxed warningNone found in compared labels
How we combine label and product data →
No current FDA shortage listed · checked Sep 23, 2026
Other forms & routes:
Pentamidine Oral Inhalation at a glance The quick version — the full detail is in the Patient Information Guide below.
💊
HelloPharmacist Editorial Team Bottom Line
Pentamidine isethionate is a specialized antiprotozoal medication used specifically in HIV-infected patients — the inhaled NebuPent form prevents PJP lung infections, while Pentam 300 injection treats active PJP. It requires careful medical monitoring because of serious potential risks including dangerously low blood pressure, low blood sugar, and heart rhythm problems. Always use it exactly as prescribed and report any unusual symptoms to your healthcare provider right away.

📖 Pentamidine Oral Inhalation: Patient Information Guide

A plain-language walkthrough of Pentamidine Oral Inhalation — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.

🎯What it's used for

Pentamidine isethionate is an antiprotozoal medicine used in HIV-infected patients to prevent or treat a serious fungal lung infection called Pneumocystis jiroveci pneumonia (PJP). The approved use depends on the specific product and route:

  • NebuPent (inhaled): Prevents PJP in high-risk HIV-infected patients who have already had one or more PJP episodes, or whose CD4+ T-cell count (an immune system marker) is 200/mm³ or below.
  • Pentam 300 (injection — IM or IV): Treats active PJP infections in adults and children older than 4 months of age.
⚙️How it works

Pentamidine works by attacking the Pneumocystis organism at its core. It blocks the organism's ability to make DNA, RNA, proteins, and phospholipids (fats that are essential for cell structure) — essentially shutting down the building blocks it needs to survive and replicate. Without these, the organism cannot grow or spread. The exact details of how pentamidine does this are not fully understood, but the end result is that the infection is stopped in its tracks.

💊How it's taken

How pentamidine is given depends entirely on which product is prescribed and what it's being used for. NebuPent is inhaled as a mist through a special nebulizer — it goes directly into the lungs and is not swallowed. Pentam 300 is given by a healthcare provider either as a deep muscle injection or as a slow IV infusion lasting 60 to 120 minutes — never faster, because rapid infusion raises the risk of serious low blood pressure.

  • NebuPent: inhaled via the Respirgard II nebulizer on a schedule set by your prescriber
  • Pentam 300: given once daily by IM or IV for a course of days as directed by your prescriber

Never adjust your dose or schedule on your own. If you miss a dose, contact your prescriber for guidance.

🤒Side effects — in detail

Pentamidine can cause a range of side effects — some common and manageable, others serious enough to need immediate attention.

  • Cough, wheezing, or shortness of breath
  • Fatigue and fever
  • Decreased appetite
  • Nausea, diarrhea, or stomach discomfort
  • Dizziness or light-headedness
  • Headache
  • Bad or altered taste
  • Night sweats

More serious reactions — including severe low blood pressure, dangerously low blood sugar, life-threatening heart rhythm problems, and pancreatitis — have been reported. Get medical help right away if you feel faint, have an irregular heartbeat, experience severe stomach pain, or notice signs of low blood sugar (shakiness, sweating, confusion).

⚠️Warnings & precautions
  • Life-threatening reactions have occurred with pentamidine injections, including severe low blood pressure (hypotension), very low blood sugar (hypoglycemia), acute pancreatitis, and dangerous heart rhythm problems — some fatal.
  • A severe drop in blood pressure can happen after even a single IM or IV dose. Rapid IV infusion makes this more likely. Patients receiving IV doses must be monitored closely.
  • IV administration carries a risk of extravasation — the drug leaking out of the vein into surrounding tissue. This can cause serious skin and tissue damage, including ulcers and tissue death. Surgery has been required in some cases.
  • Because of these serious risks, pentamidine injection should only be used in patients with confirmed or strongly suspected PJP.
  • Kidney damage is a known risk, especially when used alongside other drugs that can harm the kidneys.
🔀What it interacts with

Pentamidine can interact with several other medications, most importantly by adding to their harmful effects on the kidneys. Tell your prescriber and pharmacist about everything you take.

  • Aminoglycosides (such as gentamicin) — combined use raises the risk of kidney damage
  • Amphotericin B (antifungal) — increased kidney damage risk when used together
  • Cisplatin (chemotherapy) — increased kidney damage risk
  • Foscarnet (antiviral) — increased kidney damage risk; also physically incompatible with pentamidine IV solutions
  • Vancomycin (antibiotic) — increased kidney damage risk
  • Fluconazole (antifungal) — IV solutions of pentamidine are physically incompatible and must not be mixed

This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.

📋Before taking it
  • Severe allergy to pentamidine: Anyone who has had a life-threatening allergic (anaphylactic) reaction to inhaled or injected pentamidine must not use it again — this is an absolute contraindication.
  • Kidney problems: Pentamidine can affect kidney function; patients with existing kidney disease require extra caution and monitoring.
  • Other kidney-toxic medications: Tell your prescriber about all medications, especially antibiotics, antivirals, and chemotherapy agents that can harm the kidneys.
  • Pregnancy: Discuss the risks and benefits with your prescriber before using pentamidine if you are pregnant or planning to become pregnant.
  • Children: Pentam 300 injection is approved for children older than 4 months; discuss all pediatric use with the prescriber.
  • Blood sugar issues: Pentamidine can cause both low and high blood sugar — patients with diabetes or blood sugar concerns should be monitored carefully.
🚑If you take too much

Overdose with pentamidine has not been formally reported, and the specific signs are not well defined. However, a serious overdose could potentially cause the same severe, life-threatening effects seen with regular doses — such as dangerously low blood pressure, heart rhythm problems, and low blood sugar. If you suspect an overdose or accidental exposure, seek emergency medical care immediately.

🔬Pharmacokinetics — how your body processes it

After injection, pentamidine is distributed widely throughout the body and concentrates heavily in organs like the liver, kidneys, and lungs — sometimes at levels 70 to 1,000 times higher than in the blood. It has a long and variable half-life (the time it takes for the body to clear half the drug), reported between roughly 3 and 12 days, which means it can linger in tissues for weeks after treatment ends. The drug is cleared primarily through the kidneys, and patients can continue to excrete it in urine for up to 6 to 8 weeks after stopping. Because the drug builds up in the body with repeated dosing, patients with kidney problems may accumulate higher levels and require closer monitoring.

📦How to store it

store at 22° to 30°C (72° to 86°F).

📄 Written from Pentamidine Oral Inhalation’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →

🩺 Pharmacist Counseling Corner

Quick, plain-English answers to the questions patients ask most about Pentamidine Oral Inhalation — the kind of thing our pharmacy team would talk through with you at the counter.

What exactly is NebuPent used for — is it a treatment or a prevention?
NebuPent is specifically for prevention, not treatment. It's prescribed to HIV-infected patients who are at high risk of developing a serious lung infection called Pneumocystis jiroveci pneumonia, or PJP. You'd be considered high-risk if you've already had PJP before, or if your CD4+ count — a measure of how well your immune system is working — has dropped to 200 or below. If you actually have an active PJP infection, a different form of pentamidine (the injectable Pentam 300) would be used to treat it.
How do I use the inhaler — do I just breathe it in like a regular inhaler?
It's a bit different from a standard pocket inhaler. NebuPent is used with a special device called a Respirgard II nebulizer, which turns the medication into a fine mist that you slowly breathe in. Your care team should show you how to set it up and use it correctly. It's important to use the right device — don't try to substitute another nebulizer. Follow the instructions for how long each session takes and how often to do it, exactly as your prescriber directed.
What side effects should I actually expect, and which ones mean I need to call someone?
Some of the more common things people notice with NebuPent are cough, wheezing, fatigue, fever, decreased appetite, dizziness, and a bad taste in the mouth — these are unpleasant but generally manageable. The ones you really need to act on right away are: sudden dizziness or fainting (which could mean a serious drop in blood pressure), shakiness or sweating that might signal low blood sugar, a very fast or irregular heartbeat, or severe abdominal pain. Don't wait on those — get medical help immediately.
Are there any medications I shouldn't take while I'm on this?
Yes — the biggest concern is with drugs that can also harm the kidneys. That includes certain antibiotics like aminoglycosides (gentamicin, tobramycin) and vancomycin, the antifungal amphotericin B, the antiviral foscarnet, and some chemotherapy drugs like cisplatin. Using any of these alongside pentamidine raises the risk of kidney damage. Make sure every provider you see — and your pharmacist — knows you're on pentamidine so they can check for these interactions.
Is there anyone who should not use pentamidine at all?
Yes — if you've ever had a life-threatening allergic reaction (anaphylaxis) to pentamidine, whether inhaled or injected, you should not use it again in any form. That's an absolute rule. Beyond that, if you have kidney problems, blood sugar issues like diabetes, or are pregnant, you need to have an honest conversation with your prescriber before starting. These aren't necessarily reasons to avoid it completely, but they do require extra care and closer monitoring.
How long does pentamidine stay in my system after I stop?
Pentamidine sticks around for a surprisingly long time. It concentrates heavily in organs like the liver and kidneys, and the body clears it slowly — studies show people can still excrete it in their urine for up to 6 to 8 weeks after stopping. This is why monitoring during and after treatment matters, especially for kidney function. It also means drug interactions and side effects can potentially linger even after the last dose.
Is Pentamidine Oral Inhalation available over the counter?
Pentamidine Oral Inhalation is dispensed by prescription according to its FDA labeling, so it isn't sold over the counter. Your prescriber and pharmacist will determine if it's appropriate for you.
When was Pentamidine Oral Inhalation first available?
Pentamidine Oral Inhalation has been available in the United States since at least 1984, based on FDA approval history (Drugs@FDA) and product marketing records.
Who makes Pentamidine Oral Inhalation?
Pentamidine Oral Inhalation is supplied by 7 manufacturers listed in the FDA NDC Directory, including Seton Pharmaceuticals, XGen Pharmaceuticals DJB, Inc., Fresenius Kabi USA, LLC.

💬 Answers drafted from Pentamidine Oral Inhalation’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →

🧰 Keep exploring

💊 How Pentamidine Oral Inhalation comes

Pentamidine Oral Inhalation is available in 2 forms. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.

Injection

Into a muscle · Into a vein
Brands Pentam 300 Pentamidine Isethionate
How this form is used
What it may be used for
  • Pentam 300 is used to treat active Pneumocystis jiroveci pneumonia (PJP) in adults and children older than 4 months
  • Pentam 300 is given by a healthcare provider as either a deep intramuscular (IM) injection or a slow intravenous (IV) infusion
Important instructions
  • Pentam 300 IV infusion must be given slowly over 60 to 120 minutes — rapid infusion increases the risk of severe low blood pressure
  • Pentam 300 must not be mixed or reconstituted with sodium chloride (saline) solution — this causes precipitation
  • The IV site must be closely monitored during Pentam 300 infusion to prevent leakage into surrounding tissue
  • Pentam 300 IV solutions are incompatible with fluconazole and foscarnet and must not be mixed with them
Available strengths 2 strengths
11 FDA-listed product records

Inhaler

Inhaled
Brands NebuPent Pentamidine Isethionate
How this form is used
What it may be used for
  • NebuPent is used to prevent Pneumocystis jiroveci pneumonia (PJP) in high-risk HIV-infected patients
  • NebuPent is indicated for patients with a history of one or more PJP episodes or a CD4+ T-cell count of 200 or below
Important instructions
  • NebuPent is administered by inhalation using the Respirgard II nebulizer device
  • The medication is breathed in as a mist directly into the lungs — it is not swallowed
  • Follow your prescriber's instructions for how often to use NebuPent
  • Do not use NebuPent if you have had a severe allergic reaction to pentamidine in any form
Available strengths 2 strengths
8 FDA-listed product records

📊 Pentamidine Oral Inhalation across the U.S. market

How Pentamidine Oral Inhalation appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.

2
Dose forms
7
Manufacturers
3
Brand names
23
FDA-listed product records
1984
First marketed

FDA-listed product records by dose form (tablet variants merged) — FDA National Drug Code Directory. Record counts are not sales or prescription volume.

Also listed with the FDA, not a patient dose form: Powder (4) — bulk drug substance sold to compounders/manufacturers and multi-item kits. These aren’t counted in the dose-form total above.

Seton Pharmaceuticals26%
XGen Pharmaceuticals DJB, Inc.22%
Fresenius Kabi USA, LLC13%
Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc.13%
Delmar Chemicals Inc9%
Emcure Pharmaceuticals Limited9%
Other makers9%

Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.

📈 How widely Pentamidine Oral Inhalation is used

A general measure of how commonly Pentamidine Oral Inhalation is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.

Think of this as a proxy for how widely Pentamidine Oral Inhalation is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.

341
Medicaid prescriptions filled (Q1–Q4 2025)
$56,609 gross Medicaid reimbursement (before mandatory rebates — net cost is lower)

How commonly is Pentamidine Oral Inhalation prescribed? Of the 1,596 medications we measure, Pentamidine Oral Inhalation ranks #1,402 by Medicaid prescriptions — more than 12% of them.

Where Pentamidine Oral Inhalation ranks among the drugs we measure · Q1–Q4 2025 · neighbors ±5

Utilization by Pentamidine Oral Inhalation product

Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.

pentamidine isethionate 50 MG/ML Inhalation Solution

341 Medicaid prescriptions (Q1–Q4 2025) 100% of Pentamidine Oral Inhalation prescriptions shown $56,609 gross reimbursement (before rebates) ≈ $166 per prescription (gross)

Summed across the 3 of 5 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 861597

Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.

Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Pentamidine Oral Inhalation, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 3 of 5 listed Pentamidine Oral Inhalation NDCs with Medicaid activity.

🔍 Compare Pentamidine Oral Inhalation products

A representative set of FDA-listed product records for Pentamidine Oral Inhalation — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)

Showing 23 of 23 products — FDA National Drug Code Directory. See every product, package size and price: browse all 23 Pentamidine Oral Inhalation NDCs →

RxNorm Concept Web — From Ingredient to Every Form and Strength

This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.

Ingredient (IN) Pentamidine Oral Inhalation RxCUI 7994 2 dose forms · 2 strengths
  1. Dose form (SCDF) Inhalation Solution RxCUI 2108335 No current FDA listing
    Clinical drug / strength (SCD) isethionate 50 MG/ML RxCUI 861597
  2. Dose form (SCDF) Injection RxCUI 1811403 In current FDA listings
    Clinical drug / strength (SCD) isethionate 300 MG RxCUI 861601

Look up RxCUI 7994 in the RxCUI Atlas →

RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.

🏷️ Sold under these brand names

NebuPent Pentam Pentamidine Isethionate Pentam 300

🏭 Manufacturers & labelers

Seton Pharmaceuticals 6 XGen Pharmaceuticals DJB, Inc. 5 Fresenius Kabi USA, LLC 3 Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc. 3 Delmar Chemicals Inc 2 Emcure Pharmaceuticals Limited 2 PAI Holdings, LLC dba PAI Pharma 2

🔬 Where this comes from

Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.

📄
FDA-filed drug labels (SPL) Uses, dosing, warnings & side effects from SPL records retrieved through openFDA; the linked representative set can be verified on DailyMed. ✓ Linked label effective Sep 13, 2022
🏭
Forms, brands & labelersAggregated from ingredient-matched FDA National Drug Code Directory product records for Pentamidine Oral Inhalation.
📈
Real-world reportsThe FDA Adverse Event Reporting System (FAERS), served through openFDA.
🚨
Recalls & shortagesopenFDA drug-enforcement reports and the FDA drug-shortage database.
🧾 Clinical label set — FDA-filed SPL labels retained for Pentamidine Oral Inhalation after exact ingredient or ingredient-combination matching and applicable route/form matching
Clinical labels in scope
9
NDC products indexed
23
Distinct labelers/manufacturers represented
7
Linked representative label
Fresenius Kabi USA, LLC
Linked label effective
Sep 13, 2022
Composite sections available
17
Linked SPL Set ID
cc2b635e-4840-4dc3-a177-5484371680e8
Linked SPL Document ID
5fe83fb0-2b64-40a2-a996-aaa6292e661e
Open the linked representative label on DailyMed ↗

How we combine label and product data

HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 9 FDA-filed SPL label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.

Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Fresenius Kabi USA, LLC is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.

This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.