Niclosamide

Niclosamide, sold under the brand name Niclocide among others, is a medication used to treat tapeworm infestations. This includes diphyllobothriasis, hymenolepiasis, and taeniasis. It is not effective against other worms such as pinworms or roundworms. It is taken by mouth.
Side effects include nausea, vomiting, abdominal pain, and itchiness. It may be used during pregnancy and appears to be safe for the baby. Niclosamide is in the anthelmintic family of medications. It works by blocking the uptake of sugar by the worm.
Niclosamide was discovered in 1958. It is on the World Health Organization's List of Essential Medicines. It is not commercially available in the United States. It is effective in a number of other animals.
Side effects.
Side effects include nausea, vomiting, abdominal pain, constipation, and itchiness. Rarely, dizziness, skin rash, drowsiness, perianal itching, or an unpleasant taste occur. For some of these reasons, praziquantel is a preferable and equally effective treatment for tapeworm infestation.
Mechanism of action.
Niclosamide inhibits glucose uptake, oxidative phosphorylation, and anaerobic metabolism in the tapeworm.
Other applications.
Niclosamide's metabolic effects are relevant to wide ranges of organisms, and accordingly it has been applied as a control measure to organisms other than tapeworms. For example, it is an active ingredient in some formulations such as Bayluscide for killing lamprey larvae, as a molluscide, and as a general purpose piscicide in aquaculture. Niclosamide has a short half-life in water in field conditions; this makes it valuable in ridding commercial fish ponds of unwanted fish; it loses its activity soon enough to permit re-stocking within a few days of eradicating the previous population. Researchers have found that niclosamide is effective in killing invasive zebra mussels in cool waters.
Research.
Niclosamide is being studied in a number of types of cancer. Niclosamide along with oxyclozanide, another anti-tapeworm drug, was found in a 2015 study to display "strong "in vivo" and "in vitro" activity against methicillin-resistant "Staphylococcus aureus" (MRSA)".
Danish biotech company UNION is currently conducting a clinical study using niclosamide in the treatment of COVID-19.
In 2018, niclosamide was observed to be a potent activator of PTEN-induced kinase 1 in primary cortical neurons. As PINK1 dysfunction is associated with a form of Parkinson's Disease, this quality makes niclosamide and derivative compounds attractive as research tools and potential treatment avenues for the condition.
Niclosamide is also being investigated as a treatment for Covid-19 