Amphotericin B: Effects, Uses & Risks

Amphotericin B is a very effective antifungal agent. It is used to fight fungal infections. Although it is a popularly prescribed drug due to its high efficacy, at the same time it has a bad reputation due to its numerous side effects.

What is amphotericin B?

Amphotericin B is used for fungal infections, which are either located in the oral cavity or located in the digestive tract. Amphotericin B is a drug administered orally or as an injection solution that is derived from Streptomyces nodosum bacteria. The drug settles in the plasma membrane of fungi and causes complete death of any fungi in all stages of their growth in the short and long term. It has been the most effective antifungal drug for many decades, as very few fungal species are resistant to amphotericin B treatment.

Pharmacologic action

Unless side effects occur, amphotericin B should act exclusively on fungal infections that are either in the oral] cavity or located in the digestive tract. However, treatments of local fungal infections on the skin are also possible. Theoretically, amphotericin B can also fight infections in the respiratory tract or internal organs, as well as the urinary tract, but due to the large number of side effects, most doctors resort to other preparations if this is possible. Amphotericin B is administered either locally directly to the infected site (for example, on the skin or in the mouth and intestines) or in the form of an injection via the bloodstream to the target site. The mentioned frequent side effects result, among other things, from the fact that amphotericin B partially attacks not only the fungi, but also cell membranes, which belong to healthy cells in the organism. Nevertheless, due to its proven efficacy, amphotericin B is rarely dispensed with in severe cases. Normally, amphotericin B is used until the fungal infection has been demonstrably eliminated. This may be the case after only a few days, but treatment may extend over six to eight weeks.

Medical use and application

Amphotericin B is used as an antifungal agent to fight malignant fungal infections. It is used to eliminate infections with yeast fungi, which have accumulated primarily in the oral cavity and gastrointestinal tract. The treatment can be difficult for the patient, as it is usually necessary to pay attention to four times a day administration of the dose selected by the doctor. Most commonly, amphotericin B is administered orally in the form of tablets, but injectable solutions are equally available. Both variants can effectively combat both mild and severe to very severe infections. The drug can only treat acute fungal infections and is not suitable for prevention. These infections include histoplasmoses and blastomycoses, and infections with so-called sprout fungi can also be fought by amphotericin B. Molds of the type Aspergillus fumigatus are also susceptible to treatment with Amphotericin B. Interactions with other drugs are not known. Major, systemic diseases may not be treated by the use of amphotericin B. The drug is suitable in patients of all ages and may also be used with caution in pregnancy or during lactation.

Risks and side effects

Unfortunately, this is a drug with numerous side effects. Amphotericin B can cause permanent damage to the kidney. The severity of the damage depends on he total amount of drug administered, which is why amphotericin B should be given at the lowest possible doses (although this may vary from patient to patient). Furthermore, amphotericin B may cause fever or chills immediately after administration, as well as nausea and vomiting. Headache and also shifts in the body’s electrolyte balance are also among the commonly observed side effects. Liver damage and anemia occur less frequently. Muscle pain, which cannot be precisely localized, is less common. However, numerous side effects can be either reduced or completely eliminated by selecting the lowest possible dosage of amphotericin B at the start of treatment.