niclosamide

Action and Spectrum

Actions and spectrum: 

niclosamide is an anthelmintic medication used to treat parasitic worm infections. Its mechanism of action involves disrupting the energy metabolism of parasites, especially tapeworms. It interferes with their ability to generate adenosine triphosphate (ATP), an essential energy source, leading to paralysis and subsequent expulsion of the worms from the host’s body. 

The spectrum of niclosamide is primarily effective against tapeworms (cestodes), including species like Taenia solium (pork tapeworm) and Hymenolepis nana (dwarf tapeworm). It is less effective against other types of parasitic worms and is not typically used to treat infections caused by nematodes (roundworms) or trematodes (flukes). niclosamide is used for the treatment of tapeworm infections in humans and animals. 

Drug Interaction

Adverse Reaction

Frequency not defined 

Nausea 

Diarrhoea 

Dizziness 

Anorexia 

Rashes 

Pruritis 

Vomiting 

Headache 

Drowsiness 

Abdominal discomfort 

Itching 

Light headedness 

Black Box Warning

Black Box Warning: 

niclosamide does not have any black box warning. 

Contraindication / Caution

Contraindication/Caution: 

Contraindication: 

• Hypersensitivity: niclosamide should not be used by individuals who have a known hypersensitivity or allergy to the drug or any of its components. 
• Pregnancy: niclosamide is not recommended for use during pregnancy, especially during the first trimester, as its safety for the developing fetus has not been established. 
• Breastfeeding: The safety of niclosamide during breastfeeding is not well-documented. It is advisable to avoid its use while breastfeeding, and an alternative treatment may be considered. 
• Severe liver or kidney impairment: Individuals with severe liver or kidney impairment should use niclosamide with caution, as the drug may be poorly metabolized or eliminated from the body, potentially leading to increased side effects. 

Caution: 

• Pediatric use: The safety and effectiveness of niclosamide in children below a certain age or weight threshold may not be well-established. Its use in pediatric populations should be guided by a healthcare professional. 
• Gastrointestinal disorders: Individuals with severe gastrointestinal conditions or any condition that may affect the absorption of the drug should use niclosamide with caution. 
• Allergic Reactions: While rare, allergic reactions to niclosamide are possible. If you experience symptoms such as rash, itching, swelling, severe dizziness, or difficulty breathing, seek immediate medical attention.

Comorbidities: 

• Gastrointestinal Disorders: niclosamide can cause gastrointestinal side effects, including nausea, vomiting, and abdominal discomfort. Individuals with pre-existing gastrointestinal disorders, such as inflammatory bowel disease or severe gastritis, may experience exacerbated symptoms.  
• Allergies: If you have known allergies or hypersensitivities to niclosamide or any of its components, this medication should be avoided. 
• Drug Interactions: niclosamide may interact with other medications you are taking. Individuals with multiple medical conditions and medications should discuss potential drug interactions with their healthcare provider. 

Pregnancy / Lactation

Pregnancy consideration: pregnancy category: not assigned 

Lactation: excreted into human milk: unknown  

Pregnancy category: 

• Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester. 
• Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 
• Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.   
• Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits. 
• Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women. 
• Category N: There is no data available for the drug under this category. 

Pharmacology

Pharmacology: 

niclosamide is an anthelmintic medication used to treat parasitic worm infections, particularly tapeworms. Its pharmacology involves interfering with the energy metabolism of the parasites. niclosamide disrupts oxidative phosphorylation in the mitochondria of the worms, which leads to a depletion of adenosine triphosphate (ATP).

This energy depletion results in paralysis and detachment of the worms from the intestinal lining. The detached parasites are then eliminated from the body through bowel movements. niclosamide is absorbed from gastrointestinal tract, further limiting its systemic effects, and making it a targeted treatment for intestinal parasitic infections.  

Pharmacodynamics: 

• Anthelmintic effect: niclosamide exerts its anthelmintic effects by interfering with the energy metabolism of parasitic worms, particularly tapeworms. It disrupts oxidative phosphorylation in the mitochondria of the parasites, which is essential for their energy production. 
• Energy Depletion: By inhibiting oxidative phosphorylation, niclosamide causes a significant reduction in the production of adenosine triphosphate (ATP), the primary energy currency in cells. This leads to energy depletion in the parasites, making them unable to sustain their vital processes. 
• Paralysis: The parasites experience paralysis and detachment from the intestinal lining. This makes it easier for the body to eliminate the parasites through bowel movements. 
• Limited Systemic Effects: niclosamide is designed to have minimal absorption from the gastrointestinal tract, resulting in low systemic exposure. This targeted effect helps limit side effects and allows the medication to primarily act within the intestinal environment.

Pharmacokinetics: 

Absorption 

niclosamide is known for its poor oral bioavailability. It is absorbed from gastrointestinal tract after oral administration. The drug acts locally in the intestinal environment. 

Distribution 

niclosamide has limited distribution throughout the body because of its poor absorption and extensive metabolism in the gut. Its effects are primarily localized in the intestinal lumen, targeting parasitic worms. 

Metabolism 

niclosamide is subject to significant metabolism in the gastrointestinal tract. In this environment, it undergoes chemical changes, but the specifics of these metabolic pathways can vary. 

Elimination and excretion 

The majority of niclosamide and its metabolites are excreted in the feces. After interfering with parasitic worms’ energy metabolism and causing their paralysis, the worms are expelled from the body through bowel movements. 

Adminstartion

Administration: 

• Tablets: niclosamide is commonly available in tablet or chewable tablet form. These tablets should be swallowed whole with a full glass of water. 
• Fasting: niclosamide is often taken on an empty stomach, typically after an overnight fast. It is essential to follow the fasting recommendations provided by the healthcare professional. 
• Do Not Crush or Chew: niclosamide tablets should not be crushed, chewed, or broken. They should be ingested whole. 
• Completion of Treatment: It is vital to complete the full course of niclosamide treatment, even if you start feeling better before the treatment is finished. Stopping treatment prematurely can result in the recurrence of the condition or drug resistance. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: niclosamide 

Pronounced: (nye-KLO-suh-mide)  

Why do we use niclosamide? 

niclosamide is particularly effective in treating tapeworm infections, such as Taenia solium (pork tapeworm) and Taenia saginata (beef tapeworm) infections. niclosamide may be used to treat certain forms of schistosomiasis, which is a parasitic disease caused by schistosome flukes. In some cases, it is used to treat infections caused by the Echinococcus tapeworm, including hydatid disease.