Fact check: What is the maximum safe dosage of ivermectin for human consumption?

1. Summary of the results

The maximum safe dosage of ivermectin for human consumption is a topic of debate, with various sources providing different information. According to ^[1], the FDA-approved dose for human use is 150–200 µg/kg (single dose), and clinical studies have administered doses up to 800 µg/kg (single dose) and even 2000 µg/kg (single dose) without serious adverse events ^[1]. ^[2] emphasizes ivermectin’s excellent safety profile in humans but does not provide specific dosage limits ^[2]. ^[3] lists the standard therapeutic dosing for onchocerciasis (150 µg/kg) and for strongyloidiasis/threadworms (200 µg/kg) as single oral doses ^[3]. On the other hand, ^[4] and ^[5] report cases of ivermectin toxicity, with symptoms including gastrointestinal distress, confusion, ataxia, seizures, and hypotension, but do not explicitly state the maximum safe dosage ^{[4] [5]}. ^[6] reports a case of a 52-year-old Filipino male who developed multifactorial encephalopathy secondary to ivermectin toxicity and SARS-CoV2 infection, and states the maximum safe dosage as 0.2-0.3mg/kg/day, with a maximum daily dosage of 0.4mg/kg/day ^[6]. ^[7] recommends a single oral dose designed to provide approximately 200 mcg of ivermectin per kg of body weight for strongyloidiasis, and approximately 150 mcg of ivermectin per kg of body weight for onchocerciasis ^[7].

2. Missing context/alternative viewpoints

Some key points to consider are:

• The FDA-approved dose for human use is 150–200 µg/kg (single dose), but higher doses have been administered in clinical studies without serious adverse events ^[1].
• Ivermectin toxicity has been reported in cases where patients have self-medicated with supratherapeutic doses, resulting in neurological symptoms such as decrease in sensorium, restlessness, and complex visual hallucinations ^[6].
• The recommended dosage for strongyloidiasis is a single oral dose designed to provide approximately 200 mcg of ivermectin per kg of body weight, and for onchocerciasis, it is a single oral dose designed to provide approximately 150 mcg of ivermectin per kg of body weight ^[7].
• Alternative viewpoints include the potential of ivermectin as an antiviral agent against COVID-19, but the approved dose of ivermectin alone may not be the ideal dose for the treatment of COVID-19, and higher doses may be needed to achieve the desired antiviral effect ^[8].
• Missing context includes the fact that ivermectin is an inhibitor of the COVID-19 causative virus (SARS-CoV-2) in vitro, with a single treatment able to effect a ~5000-fold reduction in virus at 48 h in cell culture ^[9].

3. Potential misinformation/bias in the original statement

The original statement asks for the maximum safe dosage of ivermectin for human consumption, but does not provide context about the specific use case, such as treatment of onchocerciasis, strongyloidiasis, or COVID-19. This lack of context may lead to misinformation, as the safe dosage may vary depending on the specific use case. Additionally, ^[4] and ^[5] report cases of ivermectin toxicity, which may bias the perception of the safe dosage, as these cases involve self-medication with supratherapeutic doses ^{[4] [5]}. ^[8] and ^[9] provide alternative viewpoints on the potential of ivermectin as an antiviral agent against COVID-19, which may benefit pharmaceutical companies or researchers investigating ivermectin as a treatment for COVID-19 ^{[8] [9]}.