Methamphetamine (also known as speed, meth, crystal, crank, tina, ice) is a chemical widely known for its stimulant properties on the human body.
Methamphetamine can be taken orally, nasally, smoked or injected. Onset can be immediate (in the case of injection), or can take as long as 30-40 minutes if ingested orally. Different peoples' metabolisms work at different rates, and drug strengths vary, so there is no way of stating a "safe" or "unsafe" level of use.
Some of the effects include euphoria, hyper-excitability, extreme nervousness, accelerated heartbeat, sweating, dizziness, restlessness, insomnia, tooth grinding, incessant talking.
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