Artesunate is a medication used for the treatment of malaria, a life-threatening disease caused by parasites that are transmitted to humans through the bites of infected mosquitoes. According to the sources provided, it is not available over the counter.

The first source [1] indicates that Artesunate is a prescription drug, and it is protected by a patent, which means that only the patent holder has the right to manufacture and sell it. This implies that it is not available over the counter.

The second source [2] is from the Centers for Disease Control and Prevention (CDC), which is a national public health institute in the United States. According to the CDC, Artesunate is not available in the United States, and it is only accessible through the CDC's Malaria Hotline. This indicates that Artesunate is not available over the counter.

The third source [3] is a research article that discusses the use of Artesunate for the treatment of severe malaria in children. The article does not mention anything about Artesunate being available over the counter.

In conclusion, based on the sources provided, it is evident that Artesunate is not available over the counter. It is a prescription drug that is only accessible through authorized channels such as the CDC's Malaria Hotline. If you suspect that you have malaria or require treatment with Artesunate, it is advisable to seek medical attention from a qualified healthcare provider.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/ARTESUNATE
[2] https://www.cdc.gov/malaria/diagnosis_treatment/artesunate.html
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3321780/