Barbiturates effect the action of the brain chemical GABA in that they enhance the effect of GABA on the brain, and may even act in its place. GABA slows the activity of the brain. Enhancing its action causes sedation and sleep. In larger doses, the barbiturate may even replace the GABA in the brain. An overdose of a barbiturate can depress brain function so severely that respiration ceases and the person dies.
As discussed above, the depressant effect of barbiturates can be useful in counteracting the irritability and paranoia that can result from the use of amphetamines. Barbiturates have also been reported to be effective in alleviating the symptoms of heroin withdrawal. In the 1960s, injecting drug users were reported to have substituted barbiturates for opiates like heroin and methadone if such drugs were not available.
Available Forms of Nembutal
For human use, Nembutal was extensively marketed as sleeping tablets or capsules in the 1950s & 1960s. Even though Nembutal disappeared off the market over a decade ago, many people have old stocks which are still potent. One hundred of these capsules (100 x 100mg = 10gm of barbiturate) is a lethal dose.
Barbiturates are also well absorbed rectally and some countries have marketed forms of suppositories. ‘Nova Rectal’ in Canada is one such example. Sterile ampoules of injectable Nembutal for intramuscular and intravenous administration as a hypnotic, anti-convulsant and pre-operative sedative still find a small place in medicine in some countries including the US.