Can you drive a light quadricycle after using soft drugs such as marijuana?

The Road Traffic Act strictly prohibits driving a vehicle after using a substance with an effect similar to alcohol. Marijuana is such a substance because the psychoactive substances it contains impair psychomotor performance and the driver's concentration. This prohibition applies to drivers of all motor vehicles, including a light quadricycle, and the legal distinction between 'soft' and 'hard' drugs is irrelevant in this case.