A patient has inquired about using ivermectin to treat COVID-19. Has ivermectin been approved for the treatment of COVID-19? -JD, MASS.

M. Thomas Quail, MS Ed, RN, LNC, responds-SARS-CoV-2 is an enveloped, single-stranded positive-sense RNA virus closely related to the severe acute respiratory syndrome (SARS) virus.1 Developing new medications can take years, but some existing drugs may be repurposed against novel pathogens.2-4 Ivermectin is among those existing drugs currently being investigated as a way to prevent, treat, or inhibit SARS-CoV-2.3-5

Ivermectin is an FDA-approved prescription medication indicated to treat intestinal (nondisseminated) strongyloidiasis due to the nematode parasite Strongyloides stercoralis and onchocerciasis due to the nematode parasite Onchocerca volvulus.6 It is also used off-label for treating head lice, malaria, rosacea, and scabies.7-9 Ivermectin is generally safe and well tolerated when used as prescribed for approved indications.10

Mechanism of action

Ivermectin binds to glutamate-gated chloride ion channels in invertebrate nerve and muscle cells. This increases the permeability of the cell membrane to chloride ions with hyperpolarization of the nerve or muscle cells resulting in paralysis and death of the parasite.6,11

Adverse reactions of ivermectin include asthenia; fatigue; gastrointestinal symptoms, such as anorexia, nausea, vomiting, abdominal pain, constipation, and diarrhea; nervous system symptoms, such as dizziness, somnolence, vertigo, and tremor; and dermatologic symptoms, such as rash, pruritus, and urticaria. Overdoses have been associated with hypotension and neurologic effects such as confusion, coma, hallucinations, seizures, and death. Ivermectin may also potentiate the effects of other medications, such as benzodiazepines and barbiturates, that cause central nervous system depression.10,12

Veterinary formulations of ivermectin are anthelmintics used to treat multiple species of internal and external parasites. These formulations are dispensed in high doses and contain highly concentrated drugs and other ingredients not for human consumption.10,13

Recently, there has been an increase in patient usage and overdoses of both human and veterinary formulations of ivermectin to treat a SARS-CoV-2 infection. Some patients purchased veterinary ivermectin from feed or farm supply stores, while others received a prescription for off-label use.10 A 2021 published study in JAMA estimated that private and Medicare plan insurance providers have paid nearly $2.5 million for ivermectin prescriptions in just 1 week.14 Lind et al.15 reported ivermectin dispensing rates have increased in the US from a prepandemic average of 3,589 prescriptions per week to 39,102 prescriptions per week by January 2021. This increase in ivermectin usage is due to misleading information on social media, podcasts, talk shows, and a few poorly designed observational studies and published articles.16,17

Between 2020 and 2021, the American Association of Poison Control Centers (AAPCC) and the National Poison Data System (NPDS) reported 2,337 cases of ivermectin exposures, an increase of 260% from previous years. Of the 2,337 cases, although there were no deaths, 2% had a major effect, 17% had minor effects, and 13% were judged as potentially toxic exposures.18 The NPDS users coding manual19 defines medical outcome effects as:

* Minor effect: the patient had mild, minimally bothersome symptoms as a result of the exposure, such as drowsiness, stomach upset, skin irritation, and nausea. These symptoms or problems are resolved quickly.

* Moderate effect: serious but not life-threatening symptoms experienced as a result of an exposure, such as changes in heart rate and BP, decreased organ function, changes to blood components, and confusion. Some form of treatment is typically necessary, and most patients are seen in a hospital. These cases are followed by poison control staff until the majority of symptoms have resolved.

* Major effect: life-threatening and/or severe long-term effects, such as a decreased ability or inability to breathe, coma, seizures, dysrhythmias, and organ failure, experienced as a result of an exposure.

* Death: the patient died as a result of the exposure or as a direct complication of the exposure.

The American College of Medical Toxicology (ACMT), CDC, AAPCC, FDA, and numerous state public health officials have issued emergency health alerts to inform the public, physicians, and advanced practice clinicians (APCs) of the dangers of ivermectin.20-22 Study findings have indicated that ivermectin may exhibit antiviral activity against a wide range of RNA and some DNA viruses; inhibit the import of RNA viral proteins and enhance antiviral responses, which are enhanced when used in combination with remdesivir; inhibit SARS-CoV-2 by preventing viral proteins from entering a cell's nucleus; and that a 5-day course may reduce the duration of COVID-19.1-4,7,23

At the time of writing, the FDA has not approved ivermectin for treating any viral infections, including COVID-19, and has received warnings and alerts against its usage.6,11,21,22,24 Until more clinical trials and studies are performed and sufficient evidence-based data are collected, ivermectin is not recommended in either an inpatient or outpatient setting for the treatment of COVID-19.5

Nursing implications

Provision 4 of the American Nurses Association Code of Ethics for Nurses25 states that a nurse has authority, accountability, and responsibility for nursing practice; makes decisions; and takes actions consistent with the obligation to promote health and to provide optimal care.

If a physician or APC orders ivermectin to treat a patient with COVID, the nurse has a legal obligation to question or clarify the order with the prescriber. Suppose the clarification or explanation given by the physician or APC is not satisfactory, and the nurse believes that implementing the prescribed therapy would be detrimental to the patient. In that case, the nurse has the right to refuse to carry out the order. Before refusal, the nurse should attempt to resolve the issue through other avenues, such as resolution with top-level nursing management.

COVID-19 vaccination and boosters remain the most effective means to prevent infection and/or minimize disease symptoms. Once age-eligible, FDA-authorized COVID-19 prevention measures should be utilized as they become available.

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