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BZ Dosage
by Erowid

BZ has been adminstered through several routes, including IM, IV, oral, and inhalation (aerosol).

BZ Dosages (IM)
Threshold1-5.3 ug/kg
Light5.4-6 ug/kg
Common6-7 ug/kg
Strong7-8 ug/kg
Heavy9+ ug/kg
LD50 (Lethal Dose*)approx 250 ug/kg
(estimated LD50 for humans)

Onset : 1-4 hrs
Duration : 70-80 hrs
Normal After Effects : mild symptoms may persist for days or weeks

* LD50 = dose which will kill 50% of the tested animals.

Every individual reacts differently to every chemical.
Know your Body - Know your Mind - Know your Substance - Know your Source.

Erowid's dosage information is a summary of data gathered from users, research, and other
resources and should not be construed as recommendations. Individuals can respond
differently to the same dosage. What is safe for one can be deadly for another.

Start low with new substances.
Have trusted companion/guide/sitter/friend present and/or available.

Routes of Administration
Research on BZ conducted at Edgewood Arsenal explored the comparative efficacy of different routes of administration. The ideal route for the Army's purposes was inhalation via aerosol, which would allow the rapid, wide-scale administration of the drug during operations. Inhalation proved to be a viable route, and its tactical efficacy was confirmed in Project DORK at Fort Bragg, in which US Army volunteers were administered aerosolized BZ during training exercises.

Data is sometimes presented with reference to IM/IV dose levels, with an understood coefficient of 65% efficacy for inhalation-administered doses. Ketchum derived this value from experiments examining inhalation of BZ in an enclosed chamber. Inhalation was found to be about 65% as effective in drug delivery as the IV route, based on 80% retention of BZ by lungs and 80% absorption of the retained dose. 1

Incapacitating Dose (ID50)
While most psychoactive substances are explored for medical, mind-expanding, or recreational qualities, BZ is primarily associated with producing states of delirium and stupor. Most psychoactive drugs are described in terms of their ED50 (a measure of effective dose), but BZ is frequently described in terms of ID50 (a measure of incapacitating dose. This is a reflection of the fact that its effects are generally considered undesirable and an artifact of the military venue of most BZ research. 1

Second-Dose Effects
Experimental findings indicate that a second dose of BZ administered 2-4 weeks after a first session show acceleration of onset, heightened peak effect, and acceleration of recovery.

There are no documented BZ-related fatalities due to overdose. An approximate LD50 of 250 ug/kg in humans has been extrapolated from animal studies. Probable cause of death from a lethal overdose of BZ would be cardiac failure, although death could result from BZ's inhibition of heat dispersal mechanisms.

1.Ketchum JS. Chemical Warfare; Secrets Almost Forgotten. James S. Ketchum, MD. 2006.
2.Crowell EB, Ketchum JS. "The treatment of scopolamine-induced delirium with physostigmine". Clin Pharmacol Ther May-Jun 1967; 8:409-14.
3.Duvoisin RC, Katz R. "Reversal of central anticholinergic syndrome in man by physostigmine". JAMA. Nov 25 1968; 206(9):1963-5.