1P-LSD vs. LSD: New Research on How LSD Prodrugs Work
🧪 Is Your Tab LSD, 1P-LSD, or Something Else?
Blotter art and seller descriptions can't tell you what's on a tab. Cross-testing with multiple reagents gives you far more information than any label or single reaction.
Get LSD Test Kits →New research provides more evidence that 1P-LSD, 1cP-LSD and several related compounds can be converted into LSD after entering the body.
The study compared LSD with four N1-substituted lysergamides: 1A-LSD, 1P-LSD, 1B-LSD and 1cP-LSD. Researchers also tested LSZ, a related lysergamide with a different chemical modification.
The results help explain why compounds that interact relatively weakly with serotonin receptors in laboratory tests can still produce LSD-like effects in animals.
The studies do not prove that every LSD prodrug behaves identically in humans.
In this post:
What Is an LSD Prodrug?
A prodrug is a compound that is converted into another active substance through metabolism.
1P-LSD, 1cP-LSD, 1B-LSD, and 1A-LSD contain chemical substitutions attached to the nitrogen at the first position of the LSD molecule. Researchers have proposed that the body removes these additions, releasing LSD.
That distinction separates them from compounds such as LSZ. Although LSZ is structurally related to LSD, it does not appear to function by converting into LSD.
What the New Study Found
Researchers first measured how strongly the compounds interacted with several serotonin receptors.
The four N1-substituted compounds generally demonstrated weaker affinity or activity than LSD at the receptors researchers examined. Based on those laboratory results alone, they might have been expected to produce considerably weaker effects.
The results changed when the compounds were administered to rats trained to recognize the internal effects of LSD.
All four N1-substituted compounds eventually produced LSD-like responses. Blood analysis also detected LSD after the animals received 1A-LSD, 1P-LSD, 1B-LSD or 1cP-LSD.
That combination of behavioral and analytical evidence strongly suggests that the compounds were metabolized into LSD.
LSZ behaved differently. Researchers detected LSZ itself rather than LSD, supporting the conclusion that LSZ is active on its own.
1P-LSD Appeared to Take Longer to Produce LSD-Like Effects
Timing was one of the study's most interesting findings.
When 1P-LSD was tested 15 minutes after administration, it did not fully reproduce the response associated with LSD. When researchers waited 30 minutes, its LSD-like effect became stronger.
The researchers interpreted that delay as additional evidence that 1P-LSD must first be metabolized into LSD.
⚠️ Important Caveat: This does not establish an exact timeline for people. The study used male rats, injected doses and a behavioral model designed to identify drug-like internal cues. Human metabolism, oral absorption and individual responses may be different. The study also does not establish that equal labeled doses of LSD and an LSD prodrug will produce equal effects.
Can an LSD Test Kit Identify 1P-LSD?
Blotter artwork, packaging and a seller's description cannot determine whether a tab contains LSD, 1P-LSD, 1cP-LSD or another compound.
An LSD test kit can show whether a sample produces reagent reactions consistent with an indole or lysergamide. Cross-testing with multiple reagents provides more information than relying on one reaction.
However, reagent testing cannot conclusively distinguish every LSD prodrug from LSD or determine the precise amount on a tab.
Similar Names Don't Mean Identical Contents
What you buy isn't always what you get. Cross-test your tab with multiple reagents and compare your results to lab-verified reaction videos.
Get LSD Test Kits →The Transparency Triple Check
Anyone learning how to test LSD should understand the separate questions involved:
- Screen: Screen for applicable high-risk adulterants with the appropriate test strip (typically not necessary for LSD).
- Identify: Cross-test the sample with multiple reagents (LSD Spot Kit Package).
- Verify: Verify the reactions using lab-verified videos in the free Transparency Harm Reduction App.
The Transparency Triple Check can help evaluate whether the observed results are consistent with the expected substance. It cannot confirm that a tab contains LSD rather than a closely related lysergamide.
Identity and Potency Require Different Tests
The LSD QTest is designed to estimate the quantity of LSD in a tab or liquid sample. It is not an identification test and should only be used after screening the substance with appropriate reagents.
Safety Note: Results involving an LSD prodrug may not represent its actual identity or quantity. A potency result should not be treated as proof that an unknown tab contains LSD.
For more comprehensive identification, mail-in laboratory testing can analyze whether a submitted sample contains LSD, an LSD prodrug or another detected compound.
What the Research Actually Shows
The study strengthens the evidence that 1P-LSD, 1cP-LSD, 1B-LSD and 1A-LSD can function as LSD prodrugs in rats. It also shows that structurally related lysergamides such as LSZ may produce LSD-like effects through a different mechanism.
It does not establish that these compounds are interchangeable, equally potent or equally predictable in humans.
That uncertainty matters in both research and drug checking. Similar names and chemical structures do not guarantee identical contents, doses or effects.
Know What's on Your Tab. Test Your LSD.
Cross-test with multiple reagents, verify against lab-verified videos, and step up to lab analysis when you need definitive answers.
Explore LSD Testing Tools →Ships discreetly | Reaction videos in the free app | Lab analysis available
Related Resources
- How to Test LSD – Complete testing guide with recommended kit packages
- Reaction Video Library – Watch real-time reagent reactions to compare with your tests
- QTest Purity Test Kit Basics – How quantitative potency testing works
- Transparency Testing Lab Services – Mail-in laboratory analysis
- Our Types of Test Kits – Understanding the different testing methods available
- Safety Information – Important guidelines for safe testing practices
Sources
- Berquist, M.D., Gannon, B.M., Honeywell, K.M., Shaw, H.E., Carbonaro, T.M., Kozell, L.A., Abbas, A.I., Schutzer, W.E., Avram, M., Moran, J.H., & Fantegrossi, W.E. (2026). Interoceptive effects of N1-substituted lysergamides in rats: Role of agonist affinity at 5-hydroxytryptamine receptors and in vivo metabolism to lysergic acid diethylamide. The Journal of Pharmacology and Experimental Therapeutics, 104988. DOI: 10.1016/j.jpet.2026.104988
- PubMed record: https://pubmed.ncbi.nlm.nih.gov/42629248/
