Complete dosage information for 4F-MPH — threshold, light, common, strong, and heavy dose ranges across 2 routes of administration.
Full 4F-MPH profileImportant Safety Notice
Dosage information is for harm reduction purposes only. Individual sensitivity varies greatly. Always start with the lowest effective dose and work your way up slowly. Never eyeball doses — use a milligram scale.
Stimulant overdose from 4F-MPH is a medical emergency primarily involving cardiovascular and neurological toxicity. **Signs of overdose**: Extremely rapid or irregular heartbeat, chest pain, severe headache, dangerously elevated body temperature, seizures, agitation progressing to psychosis, confusion, and loss of consciousness. **Emergency response**: - Call emergency services immediately - Keep the person cool (remove excess clothing, apply cool water) - If seizures occur, protect the head and clear the area of hard objects - If the person loses consciousness, place in recovery position - **Do not** give the person more stimulants, caffeine, or depressants unless directed by medical professionals **Prevention**: Pre-measure doses. Avoid redosing. Stay hydrated (but don't overhydrate). Take breaks from physical activity. Monitor heart rate if possible. Have someone present who can recognize warning signs.
A common insufflated dose of 4F-MPH is 8–14 mg.
The threshold dose for 4F-MPH via insufflated is approximately 5 mg.
4F-MPH typically lasts 3–6 hours via insufflated.
4F-MPH can be taken via insufflated, oral. Each route has different dosage ranges and onset times.