Skip to Content

Pentamidine (Oral Inhalation)


(pen TAM i deen)

Index Terms

  • Pentamidine Isethionate

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution Reconstituted, Inhalation, as isethionate:

Nebupent: 300 mg (1 ea)

Brand Names: U.S.

  • Nebupent

Pharmacologic Category

  • Antifungal Agent
  • Antiprotozoal


Interferes with microbial RNA/DNA, phospholipids and protein synthesis, through inhibition of oxidative phosphorylation and/or interference with incorporation of nucleotides and nucleic acids into RNA and DNA


Inhalation: Limited systemic absorption with chronic therapy, potential accumulation and systemic effects unknown


Binds to tissues and plasma protein; high concentrations are found in the liver, kidney, adrenals, spleen, lungs, and pancreas; poor penetration into CNS; following oral inhalation, high concentrations are found in bronchoalveolar fluid

Half-Life Elimination

IV: 5 to 8 hours; IM: 7 to 11 hours; may be prolonged with severe renal impairment

Use: Labeled Indications

Prevention of Pneumocystis jirovecii pneumonia (PCP) in high-risk, HIV-infected patients either with a history of PCP or with a CD4+ count ≤200/mm3


Hypersensitivity to pentamidine isethionate or any component of the formulation

Dosing: Adult

Pneumocystis jirovecii pneumonia (PCP), prevention: Primary or secondary prophylaxis (alternative to preferred therapy): Inhalation: 300 mg once every 4 weeks via Respirgard II nebulizer (HHS [OI adult 2015])

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Pneumocystis jirovecii pneumonia (PCP), prevention:

Children ≥5 years (off-label population): Inhalation: 300 mg once every 4 weeks via Respirgard II nebulizer (HHS [OI pediatric 2013]; Redbook [AAP 2015]; Tomblyn 2009)

Adolescents (off-label population): Refer to adult dosing.

Dosing: Renal Impairment

There are no dosage adjustments provided in manufacturer’s labeling (has not been studied). Use with caution.

Dosing: Hepatic Impairment

There are no dosage adjustments provided in manufacturer’s labeling (has not been studied). Use with caution.


Reconstitute with 6 mL SWFI. Do not use sodium chloride for initial reconstitution (sodium chloride will cause precipitation). Do not mix with other nebulizer solutions.


Inhalation: Deliver via Respirgard II nebulizer until nebulizer is emptied (30-45 minutes). Administer at a flow rate of 5 to 7 L/minute from a 40 to 50 pound-per-square inch (PSI) oxygen or air source. A 40-50 PSI air compressor can be used alternatively, with a set flow rate at 5 to 7 L/minute or a set pressure of 22 to 25 PSI. Air compressors <20 PSI should not be used. Use appropriate precautions to minimize exposure to healthcare personnel; refer to individual institutional policy.


Store intact vials at 20°C to 25°C (68°F to 77°F); protect from light.

The manufacturer recommends the use of freshly prepared solutions for inhalation; however, may be stored for up to 48 hours in the vial at room temperature if protected from light.

Drug Interactions

BCG (Intravesical): Antibiotics may diminish the therapeutic effect of BCG (Intravesical). Avoid combination

BCG Vaccine (Immunization): Antibiotics may diminish the therapeutic effect of BCG Vaccine (Immunization). Monitor therapy

Cholera Vaccine: Antibiotics may diminish the therapeutic effect of Cholera Vaccine. Avoid combination

Highest Risk QTc-Prolonging Agents: QTc-Prolonging Agents (Indeterminate Risk and Risk Modifying) may enhance the QTc-prolonging effect of Highest Risk QTc-Prolonging Agents. Management: Avoid such combinations when possible. Use should be accompanied by close monitoring for evidence of QT prolongation or other alterations of cardiac rhythm. Consider therapy modification

MiFEPRIStone: May enhance the QTc-prolonging effect of QTc-Prolonging Agents (Indeterminate Risk and Risk Modifying). Management: Though the drugs listed here have uncertain QT-prolonging effects, they all have some possible association with QT prolongation and should generally be avoided when possible. Consider therapy modification

Moderate Risk QTc-Prolonging Agents: QTc-Prolonging Agents (Indeterminate Risk and Risk Modifying) may enhance the QTc-prolonging effect of Moderate Risk QTc-Prolonging Agents. Monitor therapy

Sodium Picosulfate: Antibiotics may diminish the therapeutic effect of Sodium Picosulfate. Management: Consider using an alternative product for bowel cleansing prior to a colonoscopy in patients who have recently used or are concurrently using an antibiotic. Consider therapy modification

Typhoid Vaccine: Antibiotics may diminish the therapeutic effect of Typhoid Vaccine. Only the live attenuated Ty21a strain is affected. Management: Vaccination with live attenuated typhoid vaccine (Ty21a) should be avoided in patients being treated with systemic antibacterial agents. Use of this vaccine should be postponed until at least 3 days after cessation of antibacterial agents. Consider therapy modification

Adverse Reactions


Central nervous system: Fatigue (66%), dizziness (45%)

Gastrointestinal: Decreased appetite (50%)

Infection: Infection (15%)

Respiratory: Cough (1% to 63%), dyspnea (48%), wheezing (32%), bronchospasm (≤15%)

Miscellaneous: Fever (51%)

1% to 5%:

Cardiovascular: Chest pain

Central nervous system: Headache

Dermatologic: Night sweats

Gastrointestinal: Diarrhea, dysgeusia, nausea, oral candidiasis

Hematologic & oncologic: Anemia

Infection: Herpes virus infection, herpes zoster, influenza

Respiratory: Pharyngitis (≤5%), bronchitis, sinusitis, upper respiratory tract infection

Miscellaneous: Night sweats

<1% (Limited to important or life-threatening): Abscess (oral), abdominal cramps, andominal pain, acute pancreatitis, acute rhinitis, ageusia, amnesia, anxiety, arthralgia, bacterial pneumonia, blepharitis, blurred vision, bronchitis, cerebrovascular accident, chest congestion, chest tightness, colitis, confusion, conjunctivitis, cryptococcal meningitis, cyanosis, cytomegalovirus colitis, cytomegalovirus retinitis, cytopenia, depression, dermatitis, desquamation, diabetes mellitus, dry hair, dyspnea, emotional lability, encephalitis (viral), eosinophilia, eosinophilic pneumonitis, esophageal candidiasis, esophagitis, eye pain, flank pain, gag reflex, gastritis, gastric ulcer, gingivitis, gout, hallucination, hematochezia, hemianopia, hemoptysis, hepatic insufficiency, hepatitis, hepatomegaly, herpes virus infection (pharyngeal), hiatal hernia, histoplasmosis, hyperglycemia, hyperkalemia, hypersensitivity reaction, hypertension, hyperventilation, hypocalcemia, hypoesthesia, hypoglycemia, hypotension, hypothermia, hypoxia, increased blood urea nitrogen, increased bronchial secretions, increased serum creatinine, insomnia, interstitial pneumonitis, Kaposi's sarcoma, laryngitis, laryngospasm, lethargy, lower extremity edema, melena, myalgia, mycoplasma infection, nephritis, nervousness, neuralgia, neuropathy, neutropenia, oral herpes, oral mucosa ulcer, otitis, palpitations, pancreatitis, pancytopenia, paranoia, paresthesia, peripheral neuropathy, pleurisy, pneumothorax, pruritus, pulmonary disease, rales, renal failure, renal insufficiency, renal pain, rhinitis, seizure, sepsis (central venous line-related), serious infection (extrapulmonary pneumocystosis), SIADH, sialorrhea, skin rash, splenomegaly, Stevens-Johnson syndrome, ST segment changes on ECG, syncope, tachycardia, tachypnea, temperature change, thrombocytopenia, tonsillitis, torsades de pointes, tremor, tuberculosis, unsteady gait, urinary incontinence, urticaria, vasodilation, vasculitis, ventricular tachycardia, vertigo, vomiting, xeroderma, xerostomia


Disease-related concerns:

• Asthma: Use inhalation formulation with caution in patients with asthma. May induce bronchospasm or cough, especially in patients with a smoking or asthma history (an inhaled bronchodilator prior to pentamidine may ameliorate symptoms).

• Pancreatitis: Use with caution in patients with a history of pancreatic disease or elevated amylase/lipase levels; acute pancreatitis (with fatality) has been reported. Discontinue inhalational pentamidine if signs/symptoms of acute pancreatitis occur.

• PCP: Acute PCP may develop despite aerosolized pentamidine prophylaxis. Although rare, extrapulmonary PCP disease may occur and has been associated with aerosolized pentamidine. Use appropriate precautions to minimize exposure to healthcare personnel; refer to individual institutional policy.

Other warnings/precautions:

• Adverse effects: Injection: According to the manufacturer, extent and consequence of pentamidine accumulation following chronic inhalation therapy are not known. Patients receiving pentamidine inhalation should be closely monitored for the development of serious adverse reactions that have occurred in patients receiving parenteral pentamidine, including hypotension, hypoglycemia, hyperglycemia, hypocalcemia, anemia, thrombocytopenia, leukopenia, hepatic or renal dysfunction, ventricular tachycardia (eg, torsade de pointes), pancreatitis, Stevens-Johnson syndrome, hyperkalemia and abnormal ST segment of ECG.

Monitoring Parameters

Liver function tests, renal function tests, blood glucose, serum potassium and calcium, CBC and platelets

Pregnancy Risk Factor


Pregnancy Considerations

Animal reproduction studies were not conducted by the manufacturer. Pentamidine crosses the human placenta (Fortunato 1989). Information related to fetal outcomes following maternal use of pentamidine is limited. If administered via the aerosolized route, maternal serum concentrations are lower, minimizing the exposure to the fetus (Gates 1993; Nanda 1992; Sperling 1992). Concern regarding occupational exposure and theoretical risk to pregnant health care workers has been discussed in the literature. Pregnant health care workers should avoid aerosolized exposure if possible (Conover 1988; Ito 1994; Smaldone 1991). Aerosolized pentamidine may be used as an alternative agent for the prophylaxis of Pneumocystis jirovecii pneumonia in pregnant HIV-infected women who either cannot tolerate the preferred therapy or who wish to avoid it during the first trimester of pregnancy (HHS [OI; adult] 2015).

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience cough or lack of appetite. Have patient report immediately to prescriber signs of infection, signs of liver problems (dark urine, feeling tired, lack of appetite, nausea, abdominal pain, light-colored stools, vomiting, or yellow skin or eyes), signs of kidney problems (urinary retention, blood in urine, change in amount of urine passed, or weight gain), signs of low blood sugar (dizziness, headache, fatigue, feeling weak, shaking, a fast heartbeat, confusion, hunger, or sweating), signs of high blood sugar (confusion, feeling sleepy, more thirst, hunger, passing urine more often, flushing, fast breathing, or breath that smells like fruit), signs of low calcium (muscle cramps or spasms, numbness and tingling, or seizures), signs of pancreatitis (severe abdominal pain, severe back pain, severe nausea, or vomiting), signs of high potassium (abnormal heartbeat, confusion, dizziness, passing out, weakness, shortness of breath, numbness or tingling feeling), arrhythmia, severe dizziness, passing out, bruising, bleeding, or severe loss of strength and energy (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.