Roidipedia.Compound reference & reporting
05 AUG 2026
CompoundsResearch chemical MPHP
Research chemicalCathinonePyrrolidinophenoneStimulantResearch chemical

MPHP

Also known as MPHP · 4'-Methyl-alpha-pyrrolidinohexiophenone

MPHP (4'-methyl-alpha-pyrrolidinohexiophenone) is a synthetic cathinone stimulant of the pyrrolidinophenone family, a longer-chain, ring-methylated relative of pyrovalerone and alpha-PVP. It circulated as a research chemical with no approved use. Human data is essentially absent; reported effects are anecdotal and describe a potent, long-lasting stimulant with heavy redose pressure.

01 Overview

MPHP belongs to the alpha-pyrrolidinophenone ('pyrro') cathinone class sold as a 'research chemical'. Like alpha-PVP and MDPV it is reported as a strong, focused stimulant with pronounced compulsive redosing and a high risk of stimulant psychosis on binges.

The class hazards apply in full and are amplified in the potent pyrrolidinophenones: compulsive redosing, cardiovascular strain, harsh comedown and unknown neurotoxicity. There are no controlled human studies, so figures are approximate and drawn from user reports.

02 Mechanism

Potent selective inhibitor of dopamine and noradrenaline reuptake with little serotonergic action, typical of the alpha-pyrrolidinophenone cathinones.

03 Dosing

TierDoseRouteNotes
Common5–20 mgInsufflatedFaster, stronger, highly compulsive.
Common10–30 mgOralAnecdotal; potent, easy to overshoot.

04 Effects

EffectMagnitudeEvidence
StimulationStrong energy, wakefulness and drive reported by users.Anecdotal
Increased focusTask fixation typical of the pyrrolidinophenones.Anecdotal
Appetite suppressionMarked reduction in hunger during effects.Anecdotal

05 Side effects

EffectSeverityFrequencyEvidenceCountermeasures
Compulsive redosingIntense urge to redose, driving multi-day binges.SevereMost usersAnecdotal
Stimulant psychosisParanoia, agitation and hallucinations after prolonged use.SevereOn bingesUnconfirmed
Cardiovascular strainMarked tachycardia and hypertension.SevereCommonUnconfirmed

07 References

Synthetic cathinones ('bath salts'): pharmacology and toxicologyBritish Journal of Pharmacology, 2014

08 Discussion0 comments

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This page is reference information, not medical advice. Doses and protocols are documented as they appear in the clinical literature and in practice — describing them is not a recommendation to use them. Countermeasures listed here are not a substitute for a physician. Legal status varies by jurisdiction and changes.