A doctor in Arkansas is now under investigation over reports that he had prescribed the anti-parasitic drug ivermectin to "thousands" of COVID-19 patients. The doctor also, reportedly, prescribed the drug to inmates at an Arkansas jail.

Reports of the doctor's activities were brought to light by Justice of the Peace Eva Madison during a county budget hearing earlier in the week. She said she received reports from a county employee that one of the jail's doctors has been prescribing ivermectin to infection prisoners.

Madison said the employee, who did not want to be identified for fear of retribution, was also prescribed ivermectin when he was referred to the correctional facility for his COVID-19 test.

The doctor has been identified as Dr. Robert Karas, who has been a medical services provider for the Washington County jail since 2015. Madison said she had confronted the doctor via telephone about the incident. He, reportedly, defended his actions, stating that he had also been prescribing the drug to his family and friends and "thousands" of other patients outside the jail.

Karas again defended his action during a television interview, stating that there have been no deaths inside the jail because of his prescription. He said he had been prescribing the drug to inmates, particularly high-risk patients over 40, since November of last year. The doctor added that all of the treatments he has prescribed were also "voluntary."

The Arkansas Medical Board said it has already launched an investigation into the matter. The Arkansas Department of Health is also launching its own investigation.

Since it had received reports that the broad spectrum anti-parasitic agent was being used for treating COVID-19, the U.S. Food and Drug Administration has been issuing warnings on the dangers of using the drug.

Ivermectin is primarily used to treat parasitic infections, mostly in animals. The U.S. Centers for Disease Prevention and Control also issued a similar warning, citing that it had received concerning reports of severe illness caused by the drug.

In a health advisory, the CDC said the use of the drug could result in serious side effects, including nausea, vomiting, and diarrhea. Overdose of the drug can also result in neurological effects, hypotension, seizures, coma, and even death.