this is a very intresting article, its about tests they have done on mice with GBL, you should read the whole article if you can.
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In a long-term dosing experiment in rodents, very high doses of butyrolactone showed a surprising lack of toxicity [NTIS, 1992]. The researchers gave 0, 112 and 225 mg/kg GBL to male rats; 0, 225 and 450 mg/kg GBL to female rats; and 0, 262 and 526 mg/kg GBL to both male and female mice. Scaled to human body size, these rodent dosages are about ten times what humans would use. The GBL was administered 5 days per week by gavage (stomach tube).
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At the end of 2 years (old age, for rats), the survival of male rats was 48% for the control group, 54% for the intermediate-dose group and 64% for the high-dose group. That’s right, the GBL-treated male rats lived longer! This was attributed to a decreased incidence of mononuclear leukemia. In the female rats receiving double the dose of the male rats, the survival was not significantly different between the three groups: 56%, 54% and 54% respectively. However, the body weight of the GBL-dosed females was 10-20% lower than that of the controls.
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Who said drugs are bad ?? 8)
So maybe, if we wanna live longer, we all should start using gbl/ghb on a daily basis lol.
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In the mice, body weights were reduced in both sexes, 6% in the males and 14-17% in the females. Female survival at two years (also old age for mice) was 76% in the control group, 68% in the intermediate-dose group and 76% in the high-dose group. Male survival was a disaster. Survival was 70% in the control group, 60% in the intermediate-dose group and 24% in the high-dose group. The higher mortality was attributed entirely to fighting and bite wounds inflicted during recovery from GBL-induced sedation. At week 67, the high-dose males were transferred from group cages to individual cages, thus eliminating fighting-related deaths and allowing males to gain back some of their lost weight.
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What does all this mean? The predominance of strong positive effects over weak adverse effects at such high dosages establishes that GBL is fundamentally safe and potentially beneficial.
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Theres a lot more to read about this, i copied the text wich i found the most intresting to read.