I was preparing for a three hour long MRI. I visited my doctor to discuss the possibility of a sedative for the procedure. Unfortunately, due to my medical history of Substance Abuse, my doctor was skeptical about prescribing any sort of benzodiazepine. She was even nervous about giving me a barbiturate.
Chloral Hydrate
Encyclopedic
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 3 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- PubChem toxicity data
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 3 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- PubChem toxicity data
Aliases: Noctec, Somnos, Somnote, Welldorm, Mickey finn, chloral-hydrate, aquachloral
Summary
Chloral hydrate is one of the oldest sedative-hypnotics, first synthesized in 1832. It has a very narrow therapeutic window and overdose can cause severe respiratory depression, cardiac arrhythmias, coma, and death. Chronic use can lead to liver damage and rapid tolerance development.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral | 200mg | 200-500mg | 500-1000mg | 1000mg+ |
☠ from ≈4–10 g oral
Deaths reported (narrow lethal margin)
“Lethal dose margin is narrow: deaths have occurred with ingestions as low as ~4-10 g; overdose presents with profound CNS depression, respiratory suppression, and risk of cardiac arrhythmias.” — dose.wiki
Onset, Duration & After-effects
| ROA | Onset | Peak | Offset | Total |
|---|---|---|---|---|
| Oral | 20-60 min | 1-2 hrs | 2-6 hrs | 5-10 hrs |
| Rectal | 15-45 min | 1-2 hrs | 2-6 hrs | 5-10 hrs |
Tolerance
Build-up
varies by mechanism; therapeutic tolerance may develop over weeks of regular use
Reset
Falls after you stop, at a rate that varies from person to person. If you've been using regularly, cut down gradually with medical help rather than stopping suddenly.
No tolerance chart. Our decay curves for these drugs were estimates, and a curve can make tolerance look longer-lasting than it is, which is the dangerous direction.
How fast tolerance to these drugs fades after a break has not been measured well enough to draw, so don't count on a dose you used to take still being safe: after time off, start with a much smaller amount and don't use alone. Mixing sedatives with each other, with alcohol or with opioids sharply raises the risk of a fatal overdose. If you've been using regularly, don't stop suddenly: withdrawal from benzodiazepines, alcohol or GHB/GBL can cause seizures or delirium, so get medical help to cut down gradually.
Sources: FRANK: benzodiazepines · Alcohol and Drug Foundation: GHB · FDA 2020: benzodiazepine boxed warning · FDA 2019: gabapentinoids and breathing · NHS: alcohol use disorder
Effects
Aggregated from 7 single-substance Erowid experience reports; 3 Erowid reports where another drug was taken too are left out
Each bar shows the share of analyzed reports whose text mentions that effect — a mention is not always a first-hand experience (fear of an effect or something witnessed can count). Mentions saying the effect did not happen are left out; that check reads keywords, so it can miss some. The shaded band on a bar, and the small range after its number, is the 95% interval: where the share could plausibly be with other reports of the same kind. Fewer reports, wider band. Tap or hover any number for details. The second value is the Bluelight extractor's per-effect confidence; a dash means the row is Erowid-derived, which has no confidence measurement.
Too few reports for bars: these effects come from 7 single-substance Erowid reports, and a bar is drawn only from 20 reports or more. With fewer, a percentage cannot tell a common effect from a rare one. Counts are shown instead. Why 20?
Effect glossary — · full glossary
Positive Effects 2
5 of 7
–
4 of 7
–
Adverse Effects 0
Also reported in combinations. In the 3 Chloral Hydrate reports where another drug was taken too, 1 mentions hospital, emergency services or an overdose, 0 a seizure and 0 psychosis (too few reports for percentages). In the 7 single-substance reports: 2, 1 and 0. These are not in the figures above: they cannot be put down to Chloral Hydrate alone, and a mention is not always something that happened to the writer.
Community Trip Reports
Anecdotal first-person accounts from Reddit, Erowid, Bluelight, and Dose.wiki. Click a source to expand. Reports are harm-reduction context, not medical guidance. Tags summarise each author's own verdict — how reports are classified.
Erowid 6 reports 4 neutral 2 cautionary visit
I have always been enamored with the pharmaceuticals of the past. Leading me to study pharmacology in college. I had always heard stories of the 'holy grail' sedative/hypnotics such as Qualuudes, Placidyl, Seconal, Chloral Hydrate, etc.
I think I first heard about chloral hydrate in context with the death of Marilyn Monroe and Anna Nicole Smith's death. I always planed to synthesize it because it seems like a pretty simple process and the precursors are not hard to get (bleach, alcohol etc) and also I thought it's pretty safe to use, because it's used...
[Erowid Note: The dose described in this report is very high, potentially beyond Erowid's 'heavy' range, and could pose serious health risks or result in unwanted, extreme effects.
I have severe insomnia. I have taken all the benzos including halcion, rophynol, versed, etc. I have tried all the non narcotic ones like Ambien, Lunesta, etc, Also some stronger sleep aids like sonata.
Chloral Hydrate Equals Tranquility While searching the vaults for info on this drug, I decided I ought to submit my personal experience since there isnt anything out here about it.
Bluelight 2 threads 2 neutral visit
Since there is so little info on this one beyond "it is better than benzos" or "its useless", I decided I'll document my experience with it last night. Apologies in advance for the berevity of the report.
I came across some crystalline chloral hydrate and dissolved about 200 mg in a half-cup or so of water. When I took a sip I immediately felt my face flush and my vision darkened a little. It's been about 15 minutes since then, and I've finished drinking it all.
Chloral Hydrate's nerd page
Pharmacology, chemical data, effect profiles, and more
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Helpful Links
Add to PsychonautWiki Journal
The PsychonautWiki Journal logging app doesn't include every substance. To track Chloral Hydrate there, start adding an ingestion, search for the name, and choose to add it as a custom substance. Paste these values:
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Import this file as custom substances
and you get "Chloral Hydrate (Substance Search)" with every
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Name
Chloral Hydrate
Unit
mg
Description
Chloral Hydrate Source: SubstanceSearch (substancesearch.com) Oral dose (mg): light 200 · common 200-500 · strong 500-1000 · heavy 1000+ Oral duration: onset 0.33-1h · peak 1-2h · offset 2-6h · total 5-10h · after-effects 24h Rectal duration: onset 15-45m · peak 1-2h · offset 2-6h · total 5-10h · after-effects 24h Note: ranges are harm-reduction guidance, not a prescription. Start low, go slow, and test your substances.
Tip: for quicker logging you can also add a Custom Unit in the app, e.g. common dose ~ 350 mg (Oral).
The app keeps custom substances simple, so the full dose ranges live in the description text above. Ranges are harm-reduction guidance, not a prescription.
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