Drug information of Posaconazole

Posaconazole

Drug group:

Posaconazole is an antifungal medicine that fights certain infections caused by fungus. Posaconazole is used to prevent fungal infections in people who have a weak immune system resulting from certain treatments or conditions (such as chemotherapy, stem cell transplantation, HIV infection, and others).
Posaconazole is also used to treat oral thrush (yeast infection of the mouth).

Mechanism of effect

Interferes with fungal cytochrome P450 (lanosterol-14α-demethylase) activity, decreasing ergosterol synthesis (principal sterol in fungal cell membrane) and inhibiting fungal cell membrane formation.

Pharmacodynamic

Posaconazole is an antifungal agent structurally related to itraconazole.

Pharmacokinetics

Absorption:Oral suspension: Unpredictable and variable (optimal absorption with a high-fat meal in 4 divided doses; absorption may be sufficient if taken with a nutritional supplement or acidic beverage [eg, ginger ale]).
Tablet (delayed-release): Predictable (preferably administered with food, but absorption is sufficient under fasting conditions).
Not significantly metabolized. Excretion:Feces 71% (~66% of the total dose as unchanged drug); urine 13% (<0.2% of the total dose as unchanged drug) Protein Binding:>98%; predominantly bound to albumin Half-Life Elimination:Suspension: 35 hours (range: 20 to 66 hours); Tablets: 26 to 31 hours; Injection: ~27 hours

Drug indications

fungal infections

Dosage

Usual Adult Dose for Aspergillosis
- Invasive IV: Loading dose: 300 mg IV twice a day on the first day Maintenance dose: 300 mg IV once a day, starting on the second day Oral: Delayed-release tablets: -Loading dose: 300 mg orally twice a day on the first day
-Maintenance dose: 300 mg orally once a day, starting on the second day Oral suspension: 200 mg orally three times a day Usual Adult Dose for Oral Thrush Oral suspension: Oropharyngeal candidiasis:
-Loading dose: 100 mg orally twice a day on the first day -Maintenance dose: 100 mg orally once a day for 13 days

Alerts

1-Hepatic effects: Hepatic dysfunction has occurred, ranging from mild/moderate increases of ALT, AST, alkaline phosphatase, total bilirubin, and/or clinical hepatitis to severe reactions (cholestasis, hepatic failure including death).
2-Use caution in patients with an increased risk of arrhythmia (long QT syndrome, concurrent QTc-prolonging drugs metabolized through CYP3A4, hypokalemia). Development of QTc prolongation, including torsade de pointes, has been reported.
Correct electrolyte abnormalities (eg, potassium, magnesium, and calcium) before initiating therapy.

Points of recommendation

-Take delayed-release tablets with food to enhance absorption and optimize plasma levels; swallow whole (do not divide, crush, or chew); use only for the prophylaxis indication.
-Take each dose of the oral suspension during or within 20 minutes after a full meal to enhance absorption and optimize plasma levels; shake well before use.
-In patients unable to eat a full meal, and the delayed-release tablets or injection are not options, give each dose of the oral suspension with a liquid nutritional supplement or an acidic carbonated beverage (e.g., ginger ale).

Pregnancy level

C

Related drugs

Voriconazole , Ketoconazole


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