What is Pentamidine?

Pentamidine is an antimicrobial medicine that attacks damaging protozoa in the body. Developed as the salt pentamidine isethionate, it is primarily used in the treatment of pneumocystis pneumonia — one of the most common HIV complications — and West African trypanosomiasis infection. It is also utilized as a preventative measure in transplant patients to safeguard the body from developing pneumocystis pneumonia. Pentamidine is sold under the brand names Nebupent® and Pentam 300®.

The process by which pentamidine is able to target and fight protozoa is not entirely known. One theory is that pentamidine initiates reactions in small regulatory proteins called ubiquitin. Although its precise biological activity is not definitively established, pentamidine is a commonly prescribed medication that falls under the class of drugs known as antiprotozoals.

Pentamidine is administered through either an injection or a process of inhalation. It is typically only given in health care settings and is rarely, if ever, prescribed for home use. The injection involves inserting a needle into the skin and introducing the pentamidine directly into the blood supply. If taken as an inhalant, a nebulizer is used to turn the medication into a fine mist, which the patient inhales; this method commonly uses an additional inhalant medication that ensures the airways stay open during the procedure.

The medication is given every four weeks or as ordered by a doctor. In general, patients notice an improvement within the first few days after the injection or inhalation. Individuals with pneumocystis pneumonia usually experience lowered fevers, clearer breathing, and improved chest x-rays when taking pentamidine.

Traditionally, pentamidine is not the first course of treatment. It is prescribed only when other drugs have failed to successfully kill the protozoa in the body. Patients who are allergic to the medications commonly prescribed may also be given the drug.

Pentamidine is known to have some noticeable side effects. Dizziness, cough, loss of appetite, nausea, vomiting, diarrhea, and the presence of a metallic taste in the mouth are among the most frequently documented side effects. There are, however, more serious side effects that could be indicative of critical health problems. These include a fruity odor to the breath, low blood pressure, sore throat, fever, and mental confusion. Though severe allergic reactions to pentamidine are uncommon, there have been a few documented cases; signs of allergic reaction are skin rash, labored breathing, dizziness, and itching or swelling — specifically itching or swelling of the face, throat, or tongue.