The opposite of overdose.

In other words, not enough to get you high.
I underdosed on mary-jane so the party sucked
by ZT May 9, 2005
When you don’t take enough meds and feel like absolute shit and feel like you are having a heart attack, a contributor to an underdose is having lollies. You will also say the first things that come to your mind and not realise what you said afterwords, you might fall asleep or just fall over passed out like because of tiredness
Jack: I’m gonna die, I’m having a underdose
by CheezyBoi_ June 7, 2021
Taking less than the prescribed medication. This can occur when people cannot afford the medication and take less than is prescribed without supervision. When the prescribed drug that has been taken does not a sufficient does because a significant amount of the active ingredients have been partially or completely removed. When patients are unable to acquire a reliable source they may reduce a prescribed dose and spread the dose out.

A drug underdose can as serious as drug overdose in that it can result in a negative state such as sickness, coma, hospitalization or death.
The problem of drug underdose has increased significantly as people stretch out their existing supply by either cutting the dose or not taking it at the prescribed time.
by mlhiss August 21, 2020
Taking less than the prescribed medication. This can occur when people cannot afford the medication and take less than is prescribed without supervision. When the prescribed drug that has been taken does not a sufficient does because a significant amount of the active ingredients have been partially or completely removed. When patients are unable to acquire a reliable source they may reduce a prescribed dose and spread the dose out.

A drug underdose can as serious as drug overdose in that it can result in a negative state such as sickness, coma, hospitalization or death.
The problem of drug underdose has increased significantly as people stretch out their existing supply by either cutting the dose or not taking it at the prescribed time.
by mlhiss August 21, 2020