A 2ml dose of chloroquine phosphate would depend on the concentration of the solution being used. Chloroquine phosphate is usually available in a solution containing 50mg/ml or 64.5mg/ml. Therefore, a 2ml dose of a 50mg/ml solution would contain 100mg of chloroquine phosphate, while a 2ml dose of a 64.5mg/ml solution would contain 129mg of chloroquine phosphate.
However, it is important to note that the use of chloroquine phosphate should only be done under the supervision of a qualified healthcare professional, as incorrect dosing can lead to serious side effects.
