Side effects of fluconazole
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Side Effects of Fluconazole
Fluconazole, a widely used antifungal medication, is generally well-tolerated but can cause a range of side effects. These side effects can vary based on the duration of treatment, dosage, and individual patient factors. Below, we explore the common and severe side effects associated with fluconazole, supported by multiple research studies.
Common Side Effects: Gastrointestinal and Skin Reactions
Gastrointestinal Issues
Gastrointestinal side effects are among the most frequently reported issues with fluconazole. In a study involving 562 children, 7.7% experienced gastrointestinal problems such as vomiting and diarrhea. Similarly, another study found that abdominal pain and headache were common adverse reactions, particularly in patients undergoing long-term treatment.
Skin Reactions
Skin-related side effects, although less common, have also been documented. In the pediatric study, 1.2% of children reported skin issues. Additionally, xerosis (dry skin) and alopecia (hair loss) were noted in 16.9% and 16.1% of patients, respectively, in a study on long-term fluconazole therapy.
Severe Side Effects: Liver, Cardiac, and Neurological Issues
Liver Toxicity
Fluconazole can cause liver enzyme elevations, which are usually transient but can be severe in some cases. Elevated alanine aminotransferase (4.9%), aspartate aminotransferase (2.7%), and alkaline phosphatase (2.3%) levels were observed in children. Another study highlighted that 7% of patients on long-term fluconazole therapy experienced increased serum transaminases, necessitating regular liver function monitoring.
Cardiac Effects
Fluconazole has been linked to cardiac issues, including QT prolongation, which can lead to Torsades de Pointes and sudden death. This is due to its inhibitory effect on the hERG K(+) channels. Additionally, a case study reported that fluconazole could augment the risk of bradycardia, especially when interacting with other medications like carvedilol and tacrolimus, leading to severe outcomes such as cardiac arrest.
Neurological Effects
Neurological side effects, although rare, can be severe. A case study reported a 54-year-old man developing polyneuropathy, lower gastrointestinal bleeding, acute renal insufficiency, and a confusional state after taking fluconazole for one month. Another study noted that patients receiving fluconazole prophylaxis after liver transplantation experienced more adverse neurological events, such as headaches, tremors, or seizures.
Drug Interactions
Fluconazole is a potent inhibitor of hepatic cytochrome P-450 enzymes, which can lead to significant drug interactions. For instance, it can increase the serum concentration of zidovudine by inhibiting its conversion to its glucuronide form, thereby increasing the risk of zidovudine-related adverse reactions. Similarly, fluconazole can elevate tacrolimus levels, leading to potential toxicity.
Conclusion
While fluconazole is generally well-tolerated, it can cause a range of side effects, from common gastrointestinal and skin reactions to severe liver, cardiac, and neurological issues. Regular monitoring and awareness of potential drug interactions are crucial for minimizing these risks.
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