Many fake or unproven medical products and methods claim to diagnose, prevent, or cure COVID-19. Fake medicines sold for COVID-19 may not contain the ingredients they claim to contain, and may even contain harmful ingredients. In March 2020, the World Health Organization (WHO) released a statement recommending against taking any medicines in an attempt to treat or cure COVID-19, although research on potential treatment was underway, including the Solidarity trial spearheaded by WHO. The WHO requested member countries to immediately notify them if any fake medicines or other falsified products were discovered. There are also many claims that existing products help against COVID-19, which are spread through rumors online rather than conventional advertising.

Anxiety about COVID-19 makes people more willing to "try anything" that might give them a sense of control of the situation, making them easy targets for scams. Many false claims about measures against COVID-19 have circulated widely on social media, but some have been circulated by text, on YouTube, and even in some mainstream media. Officials advised that before forwarding information, people should think carefully and look it up. Misinformation messages may use scare tactics or other high-pressure rhetoric, claim to have all the facts while others do not, and jump to unusual conclusions. The public was advised to check the information source's source, looking at official websites; some messages have falsely claimed to be from official bodies like UNICEF and government agencies. Arthur Caplan, head of medical ethics at New York University's medical school, had simpler advice for COVID-19 products: "Anything online, ignore it".

Products that claim to prevent COVID-19 risk give dangerous false confidence and increase infection rates. Going out to buy such products may encourage people to break stay-at-home orders, reducing social distancing. Some of the pretend treatments are also poisonous; hundreds of people have died from using fake COVID-19 treatments.

Diagnosis Medically approved tests detect the virus or the antibodies the body makes to fight it off. Government health departments and healthcare providers provide tests to the public. There have been fraudsters offering fake tests; some have offered tests in exchange for money, but others have said the test is free to collect information that could later be used for identity theft or medical insurance fraud. Some fraudsters have claimed to be local government health authorities. People have been advised to contact their doctor or genuine local government health authorities for information about getting tested. Fake tests have been offered on social media platforms, by e-mail, and by phone. Counterfeit testing kits, which were originally used for testing HIV and monitoring glucose levels, were touted as for coronavirus diagnosis. Holding one's breath for 10 seconds was claimed to be an effective self-test for the coronavirus. The WHO stated that this test did not work and should not be used. Manufacturer Bodysphere briefly sold what it claimed were coronavirus antibody tests. It falsely marketed them as having received FDA Emergency Use Authorization. It also falsely claimed they were made in the United States.

Prevention and cure claims Widely circulated rumours have made many unfounded claims about methods of preventing and curing infection with SARS-CoV-2. Among others:

Disinfection-related methods Hand cleaning methods

Hand sanitizer is not more effective than washing in plain soap and water. Washing in soap and water for at least 20 seconds is recommended by the US Centers for Disease Control and Prevention as the best way to clean hands in most situations. However, if soap and water are unavailable, a hand sanitizer containing at least 60% alcohol can be used, unless hands are visibly dirty or greasy. Soap removes coronaviruses effectively, but antibacterial soap is not better than plain soap. Red soap is not more germicidal than soaps of other colors, contrary to claims in a popular Facebook post, said Ashan Pathirana, the registrar of Sri Lanka's Health Promotion Bureau (HPB); he suggested that it might be a reference to carbolic soap. Hand sanitizer prepared at home by mixing rum, bleach, and fabric softener has been widely promoted as effective at preventing COVID-19 in YouTube videos in the Philippines. The Integrated Chemists of the Philippines (ICP) released statements saying that alcoholic drinks contain only about 40% alcohol, less than the 70% needed in effective hand sanitizers, and that mixing bleach and alcohol creates chloroform. The manufacturers of the brands of rum and bleach used in the videos have publicly issued statements calling the recipe dangerous and urging people not to use it. Vodka was alleged to be an effective homemade hand sanitizer, or an ingredient in one. The company whose brand was alleged to be protective responded to the rumours by citing the US Centers for Disease Control and Prevention statement that hand sanitizers needed to be at least 60% alcohol to be effective, and stating that their product was only 40% alcohol. Claims that vinegar was more effective than hand sanitizer against the coronavirus were made in a video that was shared in Brazil. That was disproved, as "there is no evidence that acetic acid is effective against the virus" and, even if there was, "its concentration in common household vinegar is low".

Gargling, nasal rinses, and inhalation Inhaling bleach or other disinfectants is dangerous and will not protect against COVID-19. They can cause irritation and damage to tissues, including the eyes. They are poisonous and WHO has warned not to take them internally and to keep them out of the reach of children. They are safe and effective when used to disinfect surfaces such as countertops, but are not safe for human consumption. Controversial alternative medicine proponents Joseph Mercola and Thomas Levy claimed that inhaling 0.5–3% hydrogen peroxide solution using a nebulizer could prevent or cure COVID-19. They cite research using hydrogen peroxide to sterilize surfaces, incorrectly asserts that it can therefore be used to clean human airways. A tweet from Mercola advertising this method was removed from Twitter on April 15, 2020, for violating the platform rules. Inhalation of hydrogen peroxide can cause upper airway irritation, hoarseness, inflammation of the nose, and burning sensations in the chest. At high concentrations, inhaling hydrogen peroxide can cause permanent neurological damage or death. Though hydrogen peroxide use as an alternative and complementary form of medicine is advocated for use in multiple disease processes, including COPD, asthma, pneumonia and bronchitis, there seems to be no trials regarding its use. It was reported a case of possible side effect related to chronic (during 5 years) and subacute hydrogen peroxide inhalation use which lead to interstitial lung disease in the form of acute pneumonitis. Gargling with saltwater was said to kill the coronavirus in claims on Weibo, Twitter, and Facebook. These claims were falsely attributed to respiratory expert Zhong Nanshan, Wuhan Union Hospital, and several other people and institutions, sometimes with the attribution changed and the actual advice copied verbatim. Zhong Nanshan's medical team published a refutation, pointing out that the virus settles in the respiratory tract, which cannot be cleaned by rinsing the mouth. The WHO also said it had no convincing evidence that this method would provide any protection against COVID-19. Saltwater sprays were given at the door of the River of Grace Community Church in South Korea in the false belief that this would protect people from the virus; the same unsterilized spray bottle was used on everyone, and may have increased the risk. Subsequently, 46 devotees were infected with the virus. "Corona-Cure Coronavirus Infection Prevention Nasal Spray" was fraudulently marketed online. There is no evidence that saline nasal rinses help prevent COVID-19.

Temperature

Cold weather and snow do not kill the COVID-19 virus. The virus lives in humans, not in the outdoors, though it can survive on surfaces. Even in cold weather, the body will stay at 36.5–37 degrees Celsius inside, and the COVID-19 virus will not be killed. Hot and humid conditions do not prevent COVID-19 from spreading, either. There have been many COVID-19 cases in countries with hot and humid climates. Drinking warm water or hot baths/heating to will not cure people of COVID-19. It has been claimed that these statements were made by UNICEF in coronavirus prevention guidelines, but UNICEF officials refuted this. High temperatures cannot be used on humans to kill the COVID-19 virus. Taking very hot baths can cause burns, but the body will stay at 36.5–37 degrees Celsius inside, and the COVID-19 virus will not be killed. Hot saunas and hand or hair dryers do not prevent or treat COVID-19. Steam inhalation was suggested on Facebook as a cure for coronavirus infection. Inhaling steam will not treat or cure COVID-19.

Radiation

Exposing people to sunlight will not prevent or cure COVID-19. It has been falsely claimed that UNICEF said so, in coronavirus prevention guidelines; UNICEF officials refuted this. The virus can spread in even the sunniest of weather. UV-C light cannot be used on humans to kill the COVID-19 virus. Attempting to use UV to sterilize people can cause skin irritation and damage the eyes.

Other disinfection-related methods White color does not have a 'harmful effect' on coronavirus, as claimed in a widely shared Facebook post; nor does the colour of a handkerchief have an effect on the virus, according to Ashan Pathirana, the registrar of Sri Lanka's Health Promotion Bureau (HPB). Using handkerchiefs or tissues of other colours to sneeze or cough into will be just as effective. Posts on social media claimed that volcanic ash from the eruption of the Taal Volcano on January 12, 2020, in the Philippines was the cause of low infection rates in the country, falsely stating that it could kill the virus and had "anti-viral" and "disinfectant qualities". Drinking bleach is extremely dangerous and will not protect against COVID-19. Bleach is poisonous and damages internal organs. Drinking it can cause disability and death. The WHO has warned not to drink the substance.

Protective equipment USB flash drives were being sold for $370 as a "5G Bioshield", purportedly offering protection from the non-existent threat of infection transmitted via 5G mobile telephone radio waves. Over 34,000 counterfeit surgical masks—which may have been touted as providing coronavirus prevention—were seized by Europol in March 2020. Making masks out of wet-wipes has not been officially recommended as an alternative to surgical masks, contrary to some claims. Some public health authorities have issued directions for making and using homemade cloth face masks. See face masks during the COVID-19 pandemic. Aerosol Boxes—acrylic boxes placed over patients' heads during aerosol generating procedures, such as intubation—can potentially increase dispersal of COVID-containing aerosol particles if a patient coughs.

Drugs of abuse

A mix containing amphetamines, cocaine, and nicotine, on sale on the dark web for US$300, was fraudulently presented as a vaccine against COVID-19.