Summary
N-Methylamphetamine (also known as Methamphetamine, Ma, Meth, Glass, Ice, Shard, Crank, Tina, T, Tweak, Yaba, Shabu, and Crystal) is a classical stimulant substance of the amphetamine class. It is structurally related to amphetamine, however it crosses the blood-brain barrier more rapidly, due to its relatively high lipid solubility. It produces its effects by increasing levels of the neurotransmitters serotonin, dopamine, and norepinephrine in the brain.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Smoked BA >90% | 5-10mg | 10-20mg | 20-60mg | 60mg+ |
| Oral BA ~70% | 5-10mg | 10-25mg | 25-50mg | 50mg+ |
| Insufflated BA >90% | 5-10mg | 10-30mg | 30-60mg | 60mg+ |
| Rectal BA ~99% | 5-10mg | 10-30mg | 30-40mg | 40mg+ |
| Intravenous BA ~100% | 5-10mg | 10-20mg | 20-40mg | 40mg+ |
Light
Common
Strong
Heavy
Onset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset | After Effects | Total |
|---|---|---|---|---|---|---|
| Smoked | 0-1 min | 0-0 min | 3.0-8.0 hrs | 1.0-3.0 hrs | 24.0 hrs | 1.0-3.0 hrs |
| Oral | 19-70 min | 1.0-3.0 hrs | 10.0-12.0 hrs | 3.0-4.0 hrs | 24.0 hrs | 3.0-5.0 hrs |
| Insufflated | 4-10 min | 3-4 min | 8.0-10.0 hrs | 2.0-4.0 hrs | 24.0 hrs | 1.0-3.0 hrs |
| Rectal | 4-15 min | 3-4 min | 2.0-4.0 hrs | 3.0-5.0 hrs | 12.0-24.0 hrs | - |
| Intravenous | 0-1 min | 1-1 min | 4.0-8.0 hrs | 3.0-4.0 hrs | 24.0 hrs | 4.0-8.0 hrs |
Tolerance
Build-up
develops over days to weeks of regular use
Reset
3–7 days for acute; 1–3 weeks for full reset
Cross-tolerance
Effects
Positive
- Stimulation
- Physical euphoria
Negative
- Increased heart rate
- Vasoconstriction
- Insomnia
- Teeth grinding
- Nausea
- Pupil dilation
- Increased perspiration
- Decreased appetite
Positive
- Alertness enhancement
- Euphoria
- Wakefulness
- Cognitive euphoria
- Motivation enhancement
- Focus enhancement
Negative
- Anxiety
- Talkativeness
- Time distortion
- Thought acceleration
Positive
- Increased music appreciation
- Tactile enhancement
- Increased libido
- Color enhancement
- Enhanced tactile sensation
Negative
- Light sensitivity
- Appetite suppression
- Dehydration
- Disinhibition
- Drifting