Bamisole

Mechanism of action

Bisulfite functions primarily as a reducing agent in biochemical reactions. It can donate electrons, which is essential in various metabolic processes, including the degradation of cysteine and homocysteine. The compound is involved in pathways related to amino acid metabolism, specifically influencing sulfur amino acid metabolism, which is critical in maintaining cellular redox homeostasis.

Pharmacodynamics

The pharmacodynamic properties of bisulfite include its role in reducing oxidative stress by participating in redox reactions. It helps maintain the balance of thiol groups within proteins, which is vital for their structural integrity and function. Additionally, bisulfite may influence the activity of certain enzymes involved in the metabolism of amino acids.

Pharmacokinetics

Information on the pharmacokinetics of bisulfite is limited. However, it is known to be rapidly absorbed and metabolized in the body. Its primary metabolic pathways involve the degradation of sulfur-containing amino acids. Excretion typically occurs through urine, reflecting its metabolic products.

Pregnancy

Bisulfite is not recommended during pregnancy due to potential risks, consult healthcare professionals for alternatives.

Breast-feeding

Caution is advised when using bisulfite while breastfeeding, consult with healthcare professionals before use.

Storage

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

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

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.