Niclosamide 500mg chewable tablets
Requires a prescription from a doctor or prescriber
Niclosamide is an antihelminthic used for the treatment of tapeworm infections.
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Suspected adverse reactions reported for Niclosamide
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Suspected adverse reactions reported for Niclosamide
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SNOMED CT and dm+d codes from NHS TRUD (Technology Reference data Update Distribution), licensed under the Open Government Licence v3.0. BNF code shown is the factual mapping value distributed by NHS Business Services Authority (NHSBSA) in the dm+d supplementary file under OGL v3.0; it is not affiliated with, nor licensed from, the publishers of the British National Formulary. ATC codes from the WHO Collaborating Centre for Drug Statistics Methodology (whocc.no).
Active and completed clinical studies from ClinicalTrials.gov
Source: ClinicalTrials.gov, a database of the U.S. National Library of Medicine (NLM), National Institutes of Health (NIH). Data accessed via ClinicalTrials.gov API v2. Trial information is provided for research purposes and does not constitute medical advice.
Academic studies and reviews for this medicine's active substance
Showing all 30 studies.
Reviews & meta-analyses: 9 · Randomised trials: 1 · 2023–2026
Showing all 30 studies, sorted by most relevant.
D. Wannigama, Cameron Hurst, P. Phattharapornjaroen, et al.
eClinicalMedicine, 2024
Background: Repurposed drugs with host-directed antiviral and immunomodulatory properties have shown promise in the treatment of COVID-19, but few trials have studied combinations of these agents. The aim of this trial was to assess the effectiveness of affordable, widely available, repurposed drugs used in combination for treatment of COVID-19, which may be particularly relevant to low-resource countries. Methods: We conducted an open-label, randomized, outpatient, controlled trial in Thailand from October 1, 2021, to June 21, 2022, to assess whether early treatment within 48-h of symptoms onset with combinations of fluvoxamine, bromhexine, cyproheptadine, and niclosamide, given to adults with confirmed mild SARS-CoV-2 infection, can prevent 28-day clinical deterioration compared to standard care. Participants were randomly assigned to receive treatment with fluvoxamine alone, fluvoxamine + bromhexine, fluvoxamine + cyproheptadine, niclosamide + bromhexine, or standard care. The primary outcome measured was clinical deterioration within 9, 14, or 28 days using a 6-point ordinal scale. This trial is registered with ClinicalTrials.gov (NCT05087381). Findings: Among 1900 recruited, a total of 995 participants completed the trial. No participants had clinical deterioration by day 9, 14, or 28 days among those treated with fluvoxamine plus bromhexine (0%), fluvoxamine plus cyproheptadine (0%), or niclosamide plus bromhexine (0%). Nine participants (5.6%) in the fluvoxamine arm had clinical deterioration by day 28, requiring low-flow oxygen. In contrast, most standard care arm participants had clinical deterioration by 9, 14, and 28 days. By day 9, 32.7% (110) of patients in the standard care arm had been hospitalized without requiring supplemental oxygen but needing ongoing medical care. By day 28, this percentage increased to 37.5% (21). Additionally, 20.8% (70) of patients in the standard care arm required low-flow oxygen by day 9, and 12.5% (16) needed non-invasive or mechanical ventilation by day 28. All treated groups significantly differed from the standard care group by days 9, 14, and 28 (p < 0.0001). Also, by day 28, the three 2-drug treatments were significantly better than the fluvoxamine arm (p < 0.0001). No deaths occurred in any study group. Compared to standard care, participants treated with the combination agents had significantly decreased viral loads as early as day 3 of treatment (p < 0.0001), decreased levels of serum cytokines interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1β) as early as day 5 of treatment, and interleukin-8 (IL-8) by day 7 of treatment (p < 0.0001) and lower incidence of post-acute sequelae of COVID-19 (PASC) symptoms (p < 0.0001). 23 serious adverse events occurred in the standard care arm, while only 1 serious adverse event was reported in the fluvoxamine arm, and zero serious adverse events occurred in the other arms. Interpretation: Early treatment with these combinations among outpatients diagnosed with COVID-19 was associated with lower likelihood of clinical deterioration, and with significant and rapid reduction in the viral load and serum cytokines, and with lower burden of PASC symptoms. When started very soon after symptom onset, these repurposed drugs have high potential to prevent clinical deterioration and death in vaccinated and unvaccinated COVID-19 patients. Funding: Ped Thai Su Phai (Thai Ducks Fighting Danger) social giver group.
Abstract licence: CC BY-NC-ND
B. Biersack
International Journal of Molecular Sciences, 2024
- Antifungal Agents
- Niclosamide
- Salicylanilides
Human mycoses cover a diverse field of fungal diseases from skin disorders to systemic invasive infections and pose an increasing global health problem based on ineffective treatment options, the hampered development of new efficient drugs, and the emergence of resistant fungal strains. Niclosamide is currently applied for the treatment of worm infections. Its mechanisms of action, which include the suppression of mitochondrial oxidative phosphorylation (also known as mitochondrial uncoupling), among others, has led to a repurposing of this promising anthelmintic drug for the therapy of further human diseases such as cancer, diabetes, and microbial infections. Given the urgent need to develop new drugs against fungal infections, the considerable antifungal properties of niclosamide are highlighted in this review. Its chemical and pharmacological properties relevant for drug development are also briefly mentioned, and the described mitochondria-targeting mechanisms of action add to the current arsenal of approved antifungal drugs. In addition, the activities of further salicylanilide-based niclosamide analogs against fungal pathogens, including agents applied in veterinary medicine for many years, are described and discussed for their feasibility as new antifungals for humans. Preliminary structure-activity relationships are determined and discussed. Various salicylanilide derivatives with antifungal activities showed increased oral bioavailabilities when compared with niclosamide. The simple synthesis of salicylanilide-based drugs also vouchsafes a broad and cost-effective availability for poorer patient groups. Pertinent literature is covered until 2024.
Abstract licence: CC BY
Umm-E- Laila, Zi-long Zhao, Da Xu, et al.
European journal of medicinal chemistry, 2025
- Antineoplastic Agents
- Neoplasms
- Niclosamide
Niclosamide, an FDA-approved drug traditionally used to treat parasitic infections, has garnered remarkable attention for its diverse pharmacological properties, suggesting potential therapeutic utility in oncology and a range of other diseases. This review offers an in-depth analysis of the chemical features and pharmacokinetics of niclosamide, underscoring the role of its salt forms and derivatives in enhancing bioavailability and therapeutic effectiveness. Emerging breakthroughs in nanotechnology have enabled the generation of advanced formulations capable of improving the safety and efficacy of niclosamide, addressing the challenges posed by its poor water solubility. Further, the review explores the intriguing molecular mechanisms driving niclosamide anticancer activity, highlighting its ability to act as a potent mitochondrial uncoupler and precisely modulate critical signal pathways that regulate cell proliferation, apoptosis, and inflammation. In cancer treatment, niclosamide has showcased compelling effects against various malignancies, offering marked potential in overcoming multidrug resistance, particularly in the resistant forms of leukemia and ovarian cancer. Additionally, the drug's versatility broadens its therapeutic potential beyond oncology, encompassing viral infections, metabolic disorders, and anti-inflammatory applications. By integrating the current literature, this review seeks to illuminate the pharmacological and clinical progress of niclosamide, hence emphasizing its promise as a multi-targeted therapeutic agent. As research evolves, niclosamide is poised to play a pivotal role in cancer therapy and the treatment of other complex diseases, reinforcing the necessity for continued clinical exploration and innovation.
Abstract licence: CC BY
N. S. Rejinold, Geun-woo Jin, Jin-Ho Choy
Nano Letters, 2024
- Aedes
- Chemical Engineering
- Dengue
mosquitoes stress the need for effective antivirals. No current drug effectively combats dengue efficiently. Transient immunity and severe risks highlight the need for broad-spectrum antivirals targeting all serotypes of DENV. Niclosamide, an antiparasitic, shows promising antiviral activity against the dengue virus, but enhancing its bioavailability is challenging. To overcome this issue and enable niclosamide to address the global dengue problem, nanoengineered niclosamides can be the solution. Not only does it address cost issues but also with its broad-spectrum antiviral effects nanoengineered niclosamide offers hope in addressing the current health crisis associated with DENV and will play a crucial role in combating other arboviruses as well.
Abstract licence: CC BY
Russell W. Wiggins, Jihoo Woo, Shizue Mito
Cancers, 2024
Inhibition of multiple cancer-related pathways has made niclosamide a promising candidate for the treatment of various cancers. However, its clinical application has been significantly limited by poor bioavailability. This review will discuss current findings on improving niclosamide bioavailability through modification of its chemical structure and utilization of novel nanotechnologies, like electrospraying and supercritical fluids, to improve drug delivery. For example, niclosamide derivatives, such as o-alkylamino-tethered niclosamide derivates, niclosamide ethanolamine salt, and niclosamide piperazine salt, have demonstrated increased water solubility without compromising anticancer activity in vitro. Additionally, this review briefly discusses recent findings on the first pass metabolism of niclosamide in vivo, the role of cytochrome P450-mediated hydroxylation, UDP-glucuronosyltransferase mediated glucuronidation, and how enzymatic inhibition could enhance niclosamide bioavailability. Ultimately, there is a need for researchers to synthesize, evaluate, and improve upon niclosamide derivatives while experimenting with the employment of nanotechnologies, such as targeted delivery and nanoparticle modification, as a way to improve drug administration. Researchers should strive to improve drug-target accuracy, its therapeutic index, and increase the drug's efficacy as an anti-neoplastic agent.
Abstract licence: CC BY
Mario Jug, Flavia Laffleur, Gioconda Millotti
Drug Design, Development and Therapy, 2024
- Biological Availability
- Niclosamide
- Anthelmintics
Niclosamide (NIC), an anthelmintic drug, has garnered recent attention for its potential as an antiviral, antibacterial, and chemotherapeutic agent, among other applications. Repurposing NIC presents a current trend, offering significant time and cost savings compared to developing entirely new therapeutic chemical entities. However, its drawback lies in poor solubility, resulting in notably low oral bioavailability. This review consolidates efforts to overcome this limitation by summarizing twelve categories of formulations, spanning derivatives, amorphous solid dispersions, co-crystals, nanocrystals, micelles, nanohybrids, lipid nanoparticles and emulsions, cyclodextrins, polymeric nanoparticles, dry powders for inhalation, 3D printlets, and nanofibers. These formulations cover oral, injectable, inhalable and potentially (trans)dermal routes of administration. Additionally, we present a comprehensive overview of NIC characteristics, including physico-chemical properties, metabolism, safety, and pharmacokinetics. Moreover, we identify gaps in formulation and administration pathways that warrant further investigation to address NIC poor bioavailability.
Abstract licence: CC BY-NC
Sanoj Rejinold N, Goeun Choi, Geun-woo Jin, et al.
Small (Weinheim an Der Bergstrasse, Germany), 2025
- Niclosamide
- Coronavirus Infections
- Nanotechnology
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected over 770 million people worldwide. The long-term effects of COVID-19 and their management have become important issues. Accumulating evidence indicates that post-COVID-19 syndrome, also known as long COVID, is not limited to respiratory symptoms but affects a wide range of systems, including neurological, cardiovascular, gastrointestinal, musculoskeletal, and reproductive systems etc. The social and economic losses associated with these effects are estimated to reach 3·7 trillion dollars in the United States alone. However, no treatment for long COVID has been developed. Herein, the literature on long COVID is comprehensively reviewed to examine the underlying causes. Additionally, evidence supporting the efficacy of nanoengineered niclosamide is presented, given its ability to counteract the underlying causes. Niclosamide is already Food and Drug Administration (FDA)-approved, and the nanoengineered one is a viable candidate for clinical trials for long COVID.
Abstract licence: CC BY
Zhihong Liu, Xiaofang Liang, Yu Zhang, et al.
Infection and Drug Resistance, 2024
The development of antibiotic resistance complicates the treatment of infectious diseases and is a global public health threat. However, drug repurposing can address this resistance issue and reduce research and development costs. Niclosamide is a salicylanilide compound approved by the Food and Drug Administration (FDA), and it has been used clinically for treating parasitic infections for many years. Recent studies have shown that niclosamide can inhibit bacterial and fungus activity by affecting the quorum sensing system, biofilm formation, cell membrane potential, and other mechanisms. Here, we discuss recent advances in the antimicrobial applications of niclosamide and its derivatives to provide new perspectives in treating infectious diseases.
Abstract licence: CC BY-NC
Sources: aggregated from Europe PMC (EMBL-EBI), OpenAlex, Crossref, PubMed and other open scholarly databases. Retracted articles are excluded. Study information is provided for research purposes and does not constitute medical advice.
Pharmacology and chemical data from DrugBank
Key facts
Drug status
Approved
Major interactions
None known
Half-life
Not available
Mechanism
Niclosamide works by killing tapeworms on contact.
Food interactions
None known
Human targets
1 target
Data: DrugBank · CC BY-NC 4.0
Pharmacokinetics at a glance
Absorption
Pharmacokinetic data: DrugBank · CC BY-NC 4.0
Niclosamide, once marketed in the US under the brand name Niclocide, was voluntarily withdrawn from market by Bayer in 1996.[L11860]
Known interactions with other medications. Always consult a healthcare professional.
Showing 50 of 449 interactions
How the body processes this drug — absorption, distribution, metabolism, and elimination
Enzymes involved in drug metabolism — important for understanding drug interactions
ATC P02DA01
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
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Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Linked compound data from DrugBank Open Data (CC BY-NC 4.0)
Niclosamide
Additional database identifiers
ChemSpider
4322
BindingDB
11242
PDB
VUT
ZINC
ZINC000003874496
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2623
GenAtlas
CYP2C9
GeneCards
CYP2C9
GenBank Gene Database
AY341248
Guide to Pharmacology
1326
UniProt Accession
CP2C9_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2596
GenAtlas
CYP1A2
GeneCards
CYP1A2
GenBank Gene Database
Z00036
Guide to Pharmacology
1319
UniProt Accession
CP1A2_HUMAN
DrugBank citations
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Structured knowledge from the free knowledge base
ATC classifications (Wikidata)
Linked open data from Wikidata (Q418523), a free and open knowledge base operated by the Wikimedia Foundation. Data is available under the Creative Commons CC0 1.0 Public Domain Dedication.