Date-rape drugs exist in many forms with each drug eliciting its effects through various biological mechanisms. The mechanisms of action for commonly used date-rape drugs are described in more detail below.
Gamma-hydroxybutyrate (GHB)
Overview & Background
GHB, commonly referred to as easy lay, liquid X, Georgia homeboy, liquid ecstasy, or soap, is a commonly used date-rape drug. Some forms of GHB such as sodium oxybate are used therapeutically, such as in the treatment of a sleep disorder known as narcolepsy. GHB is also one of the drugs used for detoxification and managing withdrawal in alcoholics.
GHB is a potent central nervous system (CNS) depressant. The primary means through which GHB acts is by activating specific inhibitory receptors in the brain known as gamma-Aminobutyric acid (GABAB) and GHB receptors. Through the activation of these inhibitory receptors, GHB blocks or inhibits brain signals which decreases brain activity and reduces stimulation and arousal. This leads to the behavioural effects characteristic of exposure to high doses of GHB.
Mechanism of Action
The onset of GHB’s effects occurs within 15 to 30 minutes of ingestion with effects lasting anywhere from 1 to 6 hours depending on the dose. What makes GHB even more unsafe is that its dose-effect curve is quite steep, meaning small dosage increases result in disproportionately increased behavioural effects and toxicity.
The primary reason for this is that GHB is rapidly absorbed from the gut into circulation. Typically, peak blood concentrations of GHB are reached 20 to 40 minutes following ingestion. Apart from rapid absorption, GHB is distributed rapidly into body fluids and tissues, which also explains why there is quick onset of effects.
Behavioural and physiological effects of GHB
- At low doses, GHB relaxes the person; it can make you feel less inhibited, more sociable, forgetful, weak, and lightheaded
- A slightly higher dose will enhance these effects and also cause dizziness, drowsiness, nausea and vomiting
- At high doses, an individual may become unconscious, experience seizures, a slow heartbeat, and slow breathing (i.e. difficulty breathing) which may eventually lead to a coma or death.
- The above effects are more intense when GHB is combined with alcohol or other drugs. The risk of toxic effects and overdose also increases.
Flunitrazepam (Rohypnol)
Overview & Background
Rohypnol sometimes referred to as Mexican Valium, circles, roofies, la Rocha or the forget-me pill is a frequently used date-rape drug. It is not available legally in the United States or Canada, however, in some countries, it is used as a sedative (sleeping aid), muscle relaxant, anxiolytic, or anti-convulsant.
Mechanism of Action
Like GHB, Rohypnol is a CNS depressant that belongs to a class of tranquillizers known as benzodiazepines. It binds to and activates two different receptors in the brain: BNZ1 and BNZ2. BNZ1 is a receptor that mediates sleep, thus by binding to and activating BNZ1, Rohypnol causes extreme drowsiness or blackouts. On the other hand, by binding to the BNZ2 receptor, Rohypnol causes muscle relaxation and impairs motor coordination and memory.
Rohypnol also elicits its effects by acting as a modulator at GABAA receptors which as mentioned, are inhibitory receptors also found in the brain. As a modulator, Rohypnol does not activate these receptors, rather, it increases receptors’ affinity (i.e. attraction) for their ligands (i.e. molecules which bind to receptors). Ultimately, then, Rohypnol increases action at the GABAA receptor, which results in inhibition of CNS signalling, and produces a calming effect.
Generally, after oral ingestion, Rohypnol is well absorbed and can reach peak blood concentrations in 30 to 90 minutes. Consequently, the behavioural and physiological effects of the drug manifest within 30 minutes and peak around 2 hours from the time of ingestion. However, it is important to note that even as little as 1 milligram of Rohypnol can affect you for 8 to 12 hours.
Typical effects of Rohypnol include:
- drowsiness, sleep (loss of consciousness)
- dizziness
- loss of motor control
- decreased reaction time
- impaired judgement
- lack of coordination
- slurred speech
- confusion
- loss of memory of events while under the influence (amnesia)
- respiratory depression with higher doses
Ketamine
Overview & Background
Ketamine, also known as Special K, vitamin K or cat valium is a widely used anesthetic, analgesic and antidepressant. Recently, however, Ketamine has become a commonly abused drug and is frequently used as a date-rape drug as well.
Mechanism of Action
Ketamine is a dissociative drug, meaning it makes you feel detached from reality. Although some of the biological mechanisms of Ketamine are not yet fully elucidated, it is said that Ketamine primarily antagonizes NMDA receptors which are receptors for the neurotransmitter glutamate.
Glutamate, which acts through NMDA receptors, is an excitatory neurotransmitter which means that it has stimulatory effects in the brain. By antagonizing these receptors, Ketamine inhibits neurotransmission and results in CNS depression.
Generally, the absorption of Ketamine into circulation and distribution to tissues is very rapid. As a result, behavioural and physiological effects of the drug are seen within 30 minutes of ingestion and last for 1 to 2 hours.
Common effects of Ketamine:
At smaller doses, Ketamine brings about feelings of calmness and relaxation, slurred speech, diminished reflexes and dizziness, and nystagmus (uncontrolled and repetitive eye movements)
At higher doses, Ketamine can lead to hallucinations, coma or deep unconsciousness
Alcohol
Overview & Background
Alcohol is an ethanol-containing beverage that is currently one of the most used date-rape drugs. It is often combined with other drugs, to produce synergistic effects. In essence, this means that the use of alcohol in combination with a drug causes an enhanced effect. However, alcohol alone may reduce inhibitions, impair consciousness, and affect memory as well.
Mechanism of Action
There are two widely accepted ways through which alcohol is known to elicit its effects. The first is through the increased activity of the inhibitory neurotransmitter GABA’s activity at its receptor. As mentioned, increased neurotransmission of GABA will result in inhibition of neural firing, thus, resulting in CNS depression.
Alcohol also inhibits the activity of excitatory glutamate receptors similar to Ketamine, described above. The mechanism through which this inhibition occurs is not clear, however, as mentioned above, the inhibition of excitatory receptors such as NMDA will generally lead to reduced neurotransmission of stimulatory neurotransmitters. Ultimately, then, alcohol increases CNS inhibition and decreases excitation.
Generally, alcohol is rapidly absorbed into the bloodstream with the peak blood-alcohol concentration being reached between 10- and 60-minutes following ingestion. Since alcohol is distributed into the total body water component, it can access several tissues, and elicit its effects fairly quickly.
Contributed By: Harini Kumaraverl
References
Image of GHB Mechanism Obtained from: https://faculty.washington.edu/chudler/roof.html