1P-LSD
1P-LSD (1-propionyl-LSD) is a semi-synthetic lysergamide and a research-chemical analogue of LSD. It is thought to act as a prodrug that is converted to LSD in the body, producing an experience users describe as essentially identical to LSD. It is dosed in micrograms and emerged as a legal-grey-area substitute in jurisdictions where LSD is banned.
01 Overview
1P-LSD differs from LSD by a propionyl group on the indole nitrogen and is widely believed to be metabolised to LSD, making its effects and potency very close to the parent. Reported effects include visual geometry, altered cognition, emotional intensity and time distortion over roughly 8-12 hours. There is little direct human research; the closely related LSD is far better studied.
As a lysergamide it is extremely potent, active at microgram doses, and typically distributed on blotter or in volumetric solution. Practical risks mirror LSD: a very long duration, potential for intense anxiety or difficult experiences, and the general caution around psychiatric vulnerability. Legal status shifts frequently as jurisdictions add analogue controls.
02 Mechanism
Believed to act as a prodrug converted to LSD, a high-affinity partial agonist at serotonin 5-HT2A (and other serotonin/dopamine) receptors.
03 Dosing
| Tier | Dose | Route | Notes |
|---|---|---|---|
| Threshold | 10–25 mcg | Sublingual | Sub-perceptual to mild. |
| Common | 75–150 mcg | Sublingual | Full psychedelic effect, comparable to equivalent LSD. |
| Strong | 150–300 mcg | Sublingual | Intense; higher chance of difficult experience and long duration. |
04 Effects
| Effect | Magnitude | Evidence | |
|---|---|---|---|
| Visual and perceptual effectsGeometry, colour enhancement and visual movement essentially like LSD. | Anecdotal | ||
| Cognitive and emotional intensificationAltered thought, emotional intensity and time distortion. | Anecdotal | ||
| Euphoria and introspectionPositive mood, creativity and reflection at well-judged doses. | Anecdotal |
05 Side effects
| Effect | Severity | Frequency | Evidence | Countermeasures |
|---|---|---|---|---|
| Anxiety and difficult experiencesPanic, confusion or a prolonged difficult experience, extended by the long duration. | Moderate | Common at higher doses | Anecdotal | |
| Prolonged impairment and long durationEffects last many hours with lingering impairment; unsuitable when responsibilities or driving are involved. | Moderate | Inherent to the drug | Anecdotal | |
| Latent psychiatric riskMay precipitate prolonged psychological disturbance, including in those predisposed to psychosis; HPPD (persistent visual disturbance) is also reported. | Severe | Rare | Observational |