Voriconazole is a member of the antifungals drug class, which is used to treat a variety of illnesses brought on by yeast and fungus. Any region of the body, including the mouth, throat, oesophagus, lungs, bladder, and blood, can get infected with a fungal infection. By blocking an enzyme in fungi that is necessary for their regular metabolism of fat, it hinders the growth of fungal cell membranes and stops the growth of fungus or yeast. As a result, fungal cells are destroyed. The FDA gave approval in 2002.
BRAND NAMES
Vfend - Vfend contains voriconazole as one of its active components. It is available in tablet, oral suspension, and injectable forms.
MECHANISM OF ACTION
Voriconazole inhibits cytochrome P450-dependent 14α-lanosterol demethylation, a key step in fungi's cell membrane ergosterol production.
PHARMACOKINETICS
ABSORPTION
Tmax occurs 1-2 hours after oral ingestion. When combined with a high-fat meal, Cmax drops by 34% and AUC by 24%.
DISTRIBUTION
Voriconazole has an estimated volume distribution of 4.6 litres per kilogram.
METABOLISM
Voriconazole undergoes significant hepatic metabolism via cytochrome enzymes CYO2C9, CYP2C19, and CYP3A4. N-oxidation is mediated by CYP2C19, which has an apparent KM of 14μM and an apparent Vmax of 0.22nmol/CYP2C19.
EXCRETION
Elimination of voriconazole through urine.
PHARMACODYNAMICS
Voriconazole is a fungistatic triconazole antifungal that treats infections by blocking fungal growth. It is known to produce hepatotoxicity and photosensitivity reactions in certain persons.
DOSAGE AND ADMINISTRATION
Voriconazole is available in tablet and suspension form for oral use. It is usually taken every 12 hours on an empty stomach, at least one hour before or after eating.
Voriconazole tablets are available in strengths of 50mg and 200mg.
It is available as oral suspensions at a dosage of 200mg/5ml.
This is also available in powder form for injection with a dose of 200mg.
DRUG INTERACTION
Drug interactions of voriconazole may includes
- Depression drugs – reboxetine
- Migraine drugs – ergotamine, dihydroergotamine
- GERD drugs - cisapride
- Mental illness drugs – primozide, quetiapine
- Organ transplant – sirolimus
- HIV drugs - ritonavir
CONTRAINDICATION
Voriconazole is contraindicated for hypersensitivity.
Patients with galactose intolerance, lap lactase deficiency, or impaired glucose-galactose absorption.
Co-administration with venetoclax at beginning and during the ramp-up phase in patients with chronic lymphocytic leukaemia or small lymphocytic lymphoma.
SIDE EFFECTS
Voriconazole may cause side effects may includes
- Nausea
- Vomiting
- Headache
- Dizziness
- Dry mouth
- Abnormal vision
- Flushing
Serious side effects of voriconazole may includes
- Fever
- Confusion
- Fast heartbeat
- Fast breathing
- Upset stomach
- Extreme tiredness
- Loss of appetite
- Chills
- Rash
- Sweating
- Hallucination
- Tiredness
- Lack of energy
- Yellowing of the skin
- Weight loss
- Skin peeling
- Swelling of the hands
OVERDOSE
Symptoms of overdose may includes
- Drooling
- Seizures
- Sensitivity to light
- Closed eyes
- Depression
- Shortness of breath
- Loss of balance while moving
- Extreme tiredness
- Swollen stomach
TOXICITY
Voriconazole is an antifungal medication used for the treatment and prevention of invasive fungal infections. The most prevalent adverse reactions include central nervous system damage and impaired liver function.
