VERMOFAS BOLUS

Indications

• Helminth infections
• Strongyloides infections
• Brugia malayi infections
• Wuchereria bancrofti infections
• Adjunctive therapy in colon cancer with fluorouracil

Dosage

Children: For children aged 1 month to 9 years: Initially 1 mg/kg daily in divided doses on the first day, then increased to 3

Adults: Initially 1 mg/kg daily on the first day, then increased to 6 mg/kg daily in divided doses, with the maximum dose not exceeding 9 mg/kg per day.

Mechanism of action

Levamisole exerts its antiparasitic action by acting as an agonist at L-subtype nicotinic acetylcholine receptors in the muscles of nematodes. This results in paralysis of the worms, preventing their reproductive capabilities. As an immunomodulator, Levamisole restores depressed immune functions, enhances T-cell activation, stimulates antibody formation, and increases macrophage and neutrophil activities.

Pharmacodynamics

Levamisole's pharmacodynamics are characterized by its dual role as an anthelmintic and an immunomodulator. As an anthelmintic, it specifically targets nematodes by agonizing their nicotinic acetylcholine receptors, leading to muscle paralysis. The immunomodulatory effects include activation of natural killer (NK) cells and T-cells, enhancing the host's immune response, and improving macrophage function.

Pharmacokinetics

Levamisole is rapidly absorbed after oral administration, with peak plasma concentrations occurring within 1 to 2 hours. It is extensively metabolized in the liver, and its metabolites are excreted in urine. The elimination half-life is approximately 4 to 6 hours. Care should be taken in patients with hepatic impairment, as dose adjustments may be necessary.

Contra-indications

• Blood disorders

Adverse effects

• Arthralgia (long term use)
• Diarrhoea
• Dizziness
• Headache
• Influenza-like illness (long term use)
• Insomnia (long term use)
• Myalgia (long term use)
• Nausea
• Rash (long term use)
• Seizure (long term use)
• Taste altered (long term use)
• Vasculitis (long term use)
• Vomiting

Interactions

• Levamisole moderately decreases exposure to albendazole
• Levamisole increases exposure to ivermectin

Precautions

• Epilepsy
• Sjögren’s syndrome

Pregnancy

Embryotoxic in animal studies, avoid if possible.

Breast-feeding

No information available.

Storage

Store in a cool, dry place away from direct sunlight.

Formulations

• 50 mg chewable tablets

Indications

• Dermatophyte infections
• Candidiasis
• Tinea corporis
• Tinea pedis
• Tinea cruris
• Onychomycosis

Dosage

Children: Refer to the BNF for Children for recommended dosages tailored to paediatric patients.

Adults: Refer to the appropriate clinical guidelines or BNF for specific dosing recommendations based on the type and severity of the fungal infection.

Mechanism of action

Oyclonazole exerts its antifungal activity by inhibiting the enzyme lanosterol 14-alpha-demethylase, which is involved in the biosynthesis of ergosterol. This disruption in ergosterol production affects the integrity and fluidity of the fungal cell membrane, compromising its function and leading to cell lysis.

Pharmacodynamics

The pharmacodynamics of oxyclonazole involves its fungicidal effects against a variety of fungi. Its mechanism of action results in the disruption of the cell membrane integrity, causing leakage of cellular contents and ultimately leading to cell death. The drug displays a concentration-dependent effect, with higher concentrations leading to more rapid fungicidal activity.

Pharmacokinetics

Oyclonazole is absorbed systemically following oral administration, with peak plasma concentrations occurring within a few hours. It is extensively metabolized in the liver, with an elimination half-life that allows for once-daily dosing in most cases. The drug is primarily excreted in urine, with a small fraction appearing in feces. Its pharmacokinetic profile can be influenced by factors such as hepatic function and concomitant medications.

Adverse effects

• Skin irritation
• Allergic reactions
• Nausea
• Vomiting
• Headache

Precautions

• Use with caution in patients with a history of hypersensitivity to the drug or its components.
• Monitor for adverse reactions in patients with pre-existing skin conditions.

Pregnancy

There is limited data on the use of oxyclonazole during pregnancy. It should only be used if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is unknown whether oxyclonazole is excreted in human milk. Caution is advised when administered to breastfeeding women.

Storage

Store in a cool, dry place away from light. Keep out of reach of children.

Formulations

• Topical cream
• Topical solution

Mechanism of action

The mechanism of action of levamisole as an antiparasitic agent appears to be tied to its agnositic activity towards the L-subtype nicotinic acetylcholine receptors in nematode muscles. This agonistic action reduces the capacity of the males to control their reproductive muscles and limits their ability to copulate. The mechanism of action of Levamisole as an anticancer drug in combination with fluorouracil is unknown. The effects of levamisole on the immune system are complex. The drug appears to restore depressed immune function rather than to stimulate response to above-normal levels. Levamisole can stimulate formation of antibodies to various antigens, enhance T-cell responses by stimulating T-cell activation and proliferation, potentiate monocyte and macrophage functions including phagocytosis and chemotaxis, and increase neutrophil mobility, adherence, and chemotaxis.

Pharmacodynamics

Levamisole is a synthetic imidazothiazole derivative that has been widely used in treatment of worm infestations in both humans and animals. As an anthelmintic, it probably works by targeting the nematode nicotinergic acetylcholine receptor. As an immunomodulator, it appears that Levamisole is an immunostimulant which has been shown to increase NK cells and activated T-cells in patients receiving this adjuvantly along with 5FU for Stage III colon cancer.