I first started taking recreational drugs approximately a year and a half ago. Though my experiences since then have been varied and I consider them to be quite an important portion of my life, both in the area of personal development and in garnering a rich history of enjoyable memories.
GBL
Well-documented
Well-documented
Multiple authoritative sources agree on dosing and effects.
- 5 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- 19 combo interactions documented
- PubChem toxicity data
Well-documented
Multiple authoritative sources agree on dosing and effects.
- 5 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- 19 combo interactions documented
- PubChem toxicity data
Aliases: Gamma-bl, Blue nitro, Revivarant, Renewtrient, 1,4-lactone
Summary
GBL is a prodrug rapidly converted to GHB in the body and is significantly more potent by volume than GHB. Accurate dosing with a syringe is critical as doses are measured in single milliliters. Overdose risk is high and can result in loss of consciousness, respiratory depression, and death, especially when combined with other depressants.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral BA ~95% | 0.3-0.9ml | 0.9-1.5ml | 1.5-3ml | 3ml+ |
Light
Common
Strong
Heavy
Onset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset | Total |
|---|---|---|---|---|---|
| Oral | 10-19 min | 10-30 min | 30-90 min | 1-2 hrs | 1.5-2.5 hrs |
Tolerance
Build-up
develops rapidly (prodrug for GHB — same tolerance profile)
Reset
3–7 days for acute tolerance
Tolerance Decay
Full tolerance
1d
Half tolerance
6d
Baseline
~14d
Acute tolerance: develops within a single session — the reset numbers above apply after sustained heavy use, not after one binge. Within-session tachyphylaxis usually resets largely overnight.
Tolerance builds rapidly with frequent redosing (days). After cessation, many users report substantial reduction within 3–7 days and near‑baseline in 1–2 weeks; heavy, prolonged use may prolong recovery. Cross‑tolerance is expected across GHB prodrugs. Data derive largely from HR orgs and user reports; interindividual variability is high.
Cross-Tolerances
GHB
80%
1,4-Butanediol
80%
Effects
Aggregated from 80 Erowid experience reports
Positive Effects 12
Anxiety Suppression
46.2%
70%
Euphoria
41.2%
70%
Stimulation
41.2%
70%
Tactile Enhancement
30.0%
70%
Empathy
26.2%
70%
Music Enhancement
22.5%
70%
Focus Enhancement
18.8%
70%
Sedation
17.5%
70%
Color Enhancement
12.5%
70%
Body High
8.8%
70%
Introspection
7.5%
70%
Creativity Enhancement
5.0%
70%
Adverse Effects 12
Confusion
26.2%
70%
Nausea
26.2%
70%
Sweating
12.5%
70%
Increased Heart Rate
11.2%
70%
Psychosis
7.5%
70%
Seizure
7.5%
70%
Memory Suppression
6.2%
70%
Headache
6.2%
70%
Motor Impairment
5.0%
70%
Muscle Tension
5.0%
70%
Appetite Suppression
3.8%
70%
Jaw Clenching
3.8%
70%
Combinations
Cross-Check GBL with another substanceCommunity Trip Reports
Anecdotal first-person accounts from Reddit, Erowid, and Bluelight. Click a source to expand. Reports are harm-reduction context, not medical guidance.
Erowid 8 reports 2 positive 4 neutral 2 cautionary visit
Always had trouble sleeping, so used to drink a beer or 2 to help me sleep. Then, after realising I`d piled weight on, looked for a substitute, got into legal stims, which doubled the insomnia problem. Tried 1ml of Gbl the first time, loved it, and had a nice relaxed sleep.
Some time around August last year I acquired a steady source for liter quantities of gbl. This source was out of the country and the price was good. Since this date we have had a stready supply until now, why? because I am not getting any more... I have read many great things about gbl and ghb...
Its 2:30 in the morning and I find myself undergoing a familiar scene. I'm kicking the GBL habit, again. I first discovered the stuff through a friend, and it was truly miraculous. It was the kind of drug that made me want to stand up and cheer. It could get me through any situation, no matter how unpleasant.
'Existence In A Giant, Semi-Noncorporeal Pillow' a.k.a. 'WTF you actually have some free GBL just laying around randomly?! You rule.' It was just another rave night in early '07. It was simply one of those nights where I basically have just shit run out things to do.
When I first started taking GBL I thought it was a completely harmless health supplement/healthy alcohol replacement. Before taking GBL I had little experience with other drugs except cannabis which I used to smoke daily and very heavily until I changed countries and lost my suppliers.
I am female, aged 20, and I have used GBL at doses up to (and sometimes exceeding) 20ml a day, almost every day, for the past 2 years. However, I first tried it when I was 15. This report constitutes an effort to summarize my experiences. However, it should be noted that it cannot possibly be complete.
It all started when I was out at an event with my friends. Id heard of GBL (GHB) and that theyd tried it, and it was good, but I was reluctant to try it myself. This particular day, although very apprehensive, I did try it and once I knew what I was looking for I really enjoyed the experience.
Bluelight 8 threads 8 neutral visit
Dose – 1.8ml approx Preface I’ve been a big fan of GBL for some time now. Its easy to acquire, legal (in the UK anyway), easy to dose if you know how much your gelcaps can hold and easy to administer. My first time was back in November when I had 1.5ml and loved it, but I didn’t purchase some until February.
"Existence In A Giant, Semi-Noncorporeal Pillow" a.k.a. "WTF you actually have some free GBL just laying around randomly?! You rule." It was just another rave night in early '07. It was simply one of those nights where you basically have just shit run out things to do.
GBL – Inexperienced 1st time – Sober and Solvent! Weight: 65-70kg Substances consumed: None GBL Experience: 1st Time GBL 99.9% pure: I have my doubts based on dosage below. Background: Well after the usual research … I eventually got a few doses of GBL.
Background : Not your typical GBL user, I guess. I have only drank two alcoholic beverages in my life. The last time was 8 years ago. Also not using any other drugs (or medicines for that matter). I don't like alcohol, mainly due to it's toxicity and common effects (recklessness, aggression).
Weight : 176lbs Drug : GBL erowid Dose : 2ml @ 99.98% pure (est. 3.2g GHB) T + 0min Dose 2ml GBL in about 15ml Irn-Bru. The product itself smells like nail varnish and tastes like liquorish. T + 15min Wow, This stuff is great! My head feels kind of heavy, my reactions are slow but I feel so happy and relaxed.
I weigh 130lbs. Adult male. I received 100ml of GBL last week. In a way, I wish it didn't come. First, I measured out 1ml (1cc) in an insulin syringe. I have read the dose range is 1.5-2.5ml. I put it in apple cider. It has a chemical taste, not pleasent.
Took 1.5ml at 7.30 By 7.50 I was feeling the effects, music sounded better, felt really good and scoiable. 8.00 I had a rush over my body that felt like I was having an orgasm for about 2-5mins. Then I just felt like I was drunk but completely in control.
Sex: male Weight: 11 st (70kg) Dosage: roughly 1.5ml per hour for 3 hours plus roughly 0.5ml just under an hour later result: fell asleep in pub toilet for half an hour.
Bluelight Reference Guide
GHB / 1,4-B / GBL Discussion and Use
Bluelight’s primary GHB / 1,4-B / GBL discussion thread. GBL converts to GHB in the body; same dosing/withdrawal/recovery-position considerations apply.
Read full thread on Bluelight →
GBL's nerd page
Pharmacology, chemical data, effect profiles, and more
→
Helpful Links
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