• Speed is a stimulant. It quickens the heart beat and breathing rate. • Users may feel confident. Their mind races and they feel more awake, energetic and talkative. • Effects last up to 4 hours, depending on the dose. Common effects include sweating, nausea, abdominal cramps and headache. • Speed stops the user from eating and keeps them awake. If used regularly speed can lead to weight loss and exhaustion. • The comedown (tiredness and depression) lasts for one or two days, and sometimes longer. • Taking lots of speed can make user irritable, tense, anxious and sometimes aggressive.