The classification of drugs within the legal system is a schedule. There are five levels of schedules.
Emory University explains schedules can include legal and illegal drugs. They also impact the severity of punishments you may receive for criminal convictions related to the specific schedule of drugs.
Schedule V and VI
The lowest level schedule drugs are those that are legal to possess and use as long as you have a prescription. They can easily become abusive drugs if a person does not undergo proper monitoring when using them. Both Schedule V and VI include these types of drugs.
Schedule III and II
Schedule III and II are similar to the lower two levels in that it includes prescription drugs. These require a prescription for legal use and are only for medical use.
The highest level is schedule I. These are illegal drugs. They have no medical use and are highly addictive. These drugs are the most dangerous to use as well in all instances because they have no regulation.
Even though some of the drug schedules include legal drugs, they are still illegal to possess without a proper prescription. You may face stiffer penalties, though, for possessing schedule I drugs than other drugs simply due to the fact they are completely illegal and highly dangerous.
Possession of any illegal drug or illegal possession of a legal drug could lead to misdemeanor or felony charges. The schedule does not necessarily reflect the punishment. The court will consider the circumstances of the situation, such as how much of the drug you had in your possession.