Micafungin is an antifungal medication used to treat serious fungal infections, particularly those caused by Candida species. This medication works by targeting the fungal cell wall, which is unique to fungi and not found in human cells. Precise dosing of micafungin is important to ensure both its effectiveness against the infection and the patient’s safety during treatment.
Applications of Micafungin
Micafungin is prescribed for several medical conditions, primarily various forms of candidiasis. It targets infections like candidemia, where Candida is in the bloodstream, and acute disseminated candidiasis, which involves widespread infection. It also treats Candida peritonitis and abscesses within the abdominal cavity.
The medication is also used for esophageal candidiasis, an infection affecting the esophagus. Additionally, micafungin serves as a preventive measure against Candida infections in high-risk patients, such as those undergoing hematopoietic stem cell transplantation (HSCT). Micafungin belongs to a class of antifungals called echinocandins, which inhibit the synthesis of 1,3-beta-D-glucan.
Determining the Right Micafungin Dose
Determining the appropriate micafungin dose involves several factors, including the patient’s age, weight, and the specific fungal infection being treated. This complexity ensures that patients receive the most effective and safest treatment.
For adults, standard dosages vary based on the condition. Treatment for candidemia, acute disseminated candidiasis, and Candida peritonitis and abscesses involves 100 mg per day given intravenously. For esophageal candidiasis, a higher dose of 150 mg per day is administered intravenously. When used for the prevention of Candida infections in HSCT recipients, the adult dose is 50 mg per day.
Pediatric dosing is highly individualized and considers both age and weight. For children weighing 30 kg or less with esophageal candidiasis, the recommended dose is 3 mg/kg intravenously once daily, while those over 30 kg receive 2.5 mg/kg intravenously once daily, not exceeding 150 mg per day. For candidemia, acute disseminated candidiasis, Candida peritonitis, and abscesses, children 4 months and older receive 2 mg/kg intravenously once daily, with a maximum dose of 100 mg per day. For pediatric patients younger than 4 months with candidemia without meningoencephalitis or ocular dissemination, a dosage of 4 mg/kg once daily is recommended. Prophylaxis of Candida infections in pediatric HSCT recipients is 1 mg/kg intravenously once daily, with a maximum dose of 50 mg per day.
The specific Candida species involved can influence treatment considerations, with physicians considering susceptibility to guide duration or specific approaches. Patient-specific adjustments are also considered, particularly for those with organ dysfunction. No dosage adjustment is necessary for patients with mild, moderate, or severe hepatic impairment. Similarly, no dosage adjustment is required for renal dysfunction or for patients undergoing dialysis.
Safe Administration and Considerations
Micafungin is administered as an intravenous (IV) infusion. It should be infused over at least one hour; rapid IV bolus administration is not recommended. Before use, the solution should be visually inspected for any particulate matter or discoloration, and only clear solutions should be administered.
Patients should inform their healthcare providers about all medications they are taking due to potential drug interactions. Micafungin has serious interactions with lonafarnib and Saccharomyces boulardii. It can also increase the levels of certain drugs by affecting enzyme metabolism, such as lomitapide, midazolam intranasal, and nifedipine. Healthcare providers may need to monitor or adjust the dosages of these co-administered medications.
During treatment, patients are monitored for potential side effects. This includes monitoring liver function, as micafungin can affect the liver. Kidney function may also be monitored, as impairment has been reported. Infusion-related reactions such as rash, itching, or facial swelling can occur, and if these happen, the infusion rate may be slowed.