stable in crystalline form, solutions of limited stability
Based on website reports users describe feeling of stimulation, alertness, feeling of „coming up“, urge to talk, intense connection with music. We can say that effects are similar to the effects of other substances from the cathinone group (mephedrone, methylone etc.). Onset of effects are typically seen within 5-10 min after nasal administration and 30-60 min after oral administration.
The main unwanted effects that have been reported were increased heart rate and blood pressure, teeth grinding, jaw clentching, changes in body temperature, intense sweating, insomnia. From psychological point of view they described mental confusion, poor concentration and short term memory, anxiety, paranoia, depression, psychosis and hallucinattions.
Naphyrone is usually sold as a white crystalline powder. The most common route of administration is nasal insufflation. It can be ingested in pil form or drink in water/juice, either by dabbing a moistened finger into the product or wrapping in a cigarette paper and "bombing". Users recommend a dose as small as 0.02g, by comparison with the 5-10 times higher doses associated with MDMA or mephedrone.
Naphyrone has a similar structure to pyrovalerone, which is controlled as a class C drug under the Misuse of Drugs Act of 1971. Pyrovaleron was used to treat lethargy and fatigue, but there was a high risk of abuse and addiction. Naphyrone combines properties which have psychostimulant effects and emphatogenic profiles.
Naphyrone affects reuptake of the monoamine neurotransmitters. It interacting with DA, NA and 5-HT transporters, but it doesn´t produce a release of DA or 5-HT. This triple uptake inhibitor demonstrates high potency values for inhibition of each of the neurotransmitters. Same broad effect we can see after cocaine use, but naphyrone may have approximately ten times higher potency than cocaine.
At this moment there is no study about addictive potential of naphyrone. Users are the only source of information in this case. They report craving to re-dose and lethargy.
Consistent with the known harms of the cathinones and traditional amphetamines the predicted harmful effects of naphyrone include adverse effects on the heart and blood vessels, hyperthermia, dependence liability, and psychiatric effects including psychosis and anxiety. In extreme cases amphetamine-like drugs can cause death due to cardiovascular collapse.
There are some suggestion taht naphyrone has some carcinogenic risk due to a metabolism of the naphthyl ring to a highly reactive naphthalene epoxide (Clayson, et al., 1958).
A case report 31-year-old man intoxicated with 100 mg of naphyrone powder shows typical symphatomimetic toxicity with restlessness, insomnia, anxiety, and hallucinations. Naphyrone was detected in the patient´s plasma at concentrations of 0,03 and 0,02 mg/L, 40 and 60 h after drug intake (Derungs et al., 2011).