Inhalants and GHB

Question 1

What is GHB?

Answer 1

The ‘date rape’ drug.

Question 2

What are inhalants?

Answer 2

Abused volatile liquid or gases at room temperature that do not belong to any other defined class, often from everyday household items.

Question 3

What are the different ways of using inhalants?

Answer 3

• Sniffing fumes
• Inhaling from a balloon
• Inhaling from a saturated rag
• Inhaling from a plastic or paper bag
• Aerosol cans

Question 4

What are some common inhalants?

Answer 4

Acetone, aliphatic and aromatic hydrocarbons, BCF, n-Butane, butanone (adhesives).

Question 5

The main three categories of inhalants are:

Answer 5

Volatile:

• solvents (liquid at rt, give off fumes)
• aerosols (sprays containing solvents and propellants)
• gases (domestic or anaesthetic)

All euphoriants.

Question 6

What are the acute behavioural effects of inhalants?

Answer 6

Euphoria, disinhibition, stimulation.

Then light-headedness and drowsiness (like with alcohol).

Question 7

What are the behavioural effects of heavy exposure to inhalants?

Answer 7

Slurred speech, ataxia, lethargy, hallucinations and sometimes delusions.

Question 8

What are the behavioural effects of very high doses of inhalants?

Answer 8

Anaesthesia and coma.

Question 9

Why do users tend to repeat doses of inhalants?

Answer 9

Because the hit is quite short.

Question 10

What effects can inhalants leave afterwards?

Answer 10

A ‘hangover’ and sometimes a red rash around the mouth.

Question 11

What are the risks of inhalants?

Answer 11

• Tolerance and withdrawal syndrome = dependence.
• Sudden sniffing death syndrome from cardiac arrhythmia
• Damage to lungs, kidneys and liver
• Subcortical brain anomalies
• Damage to myelin
• Vomiting and blackouts

Question 12

What are the specific risks associated with taking inhalants in a certain way?

Answer 12

• Squirting down the throat - can cause throat to swell, restricting breathing and slowing the heart.
• Inhaling from a bag - suffocation risk
• Using in combination with alcohol leads to an increased risk of death.

Question 13

What did Rosenberg et al (2002) find about drug-related subcortical anomalies?

Answer 13

Increased risk of anomalies with inhalants compared to other drugs in the basal ganglia, cerebellum, pons and thalamus. Up to about 40% of users had anomalies.

Question 14

Is solvent misuse illegal?

Answer 14

No, but illegal for shopkeepers to sell to people they think will inhale them.

Question 15

In the US, at what age does solvent abuse tend to start and peak?

Answer 15

Can start as early as in 7 year olds, peaks in 10-12 year olds.

Question 16

What did Funada et al (1992) find about the rewarding effects of toluene in mice?

Answer 16

Two compartments, in training phase one filled with toluene the other air, then in test phase observed how long spent in each chamber. Mice showed significant preference for the toluene chamber and controls showed no preference.

Question 17

Inhalants are rapidly absorbed and distributed widely around the brain. What areas of the brain are inhalants concentrated in?

Answer 17

The striatum, thalamus and deep cerebellar nuclei, as shown by Gerasimov et al (2002) with a baboon imaging study.

Question 18

What are the neural effects of inhalants?

Answer 18

Depressant effects - enhance function of GABA and glycine inhibitory receptors and inhibit excitatory NDMA glutamate receptors. This is a similar effect to alcohol, as it reduces CNS excitability. Dopamine may also be released, leading to reinforcement.

Question 19

What does GHB stand for?

Answer 19

Gamma hydroxybutyrate.

Question 20

When is GHB often used?

Answer 20

It’s a ‘club drug’ like ecstasy and ketamine, and is notorious for its use as the ‘date rape’ drug.

Question 21

What is the clinical use of GHB?

Answer 21

Used to treat cataplexy in narcoleptics.

Question 22

What other drugs are used in date rape, in addition to GHB?

Answer 22

Ketamine (hallucinogen) and rohypnol (benzodiazepine).

Question 23

What are the behavioural effects of low doses of GHB?

Answer 23

Mild euphoria, disinhibition and relaxation.

Question 24

What are the behavioural effects of high doses of GHB?

Answer 24

Slurred speech, ataxia, lehargy, dizziness, nausea and vomiting.

Question 25

What are the effects of overdosing on GHB?

Answer 25

Respiratory depression, loss of consciousness and seizures.

Question 26

What is the evidence for GHB tolerance?

Answer 26

• Informal reports of increasing dose
• Withdrawal symptoms - insomnia, anxiety and tremors (or even hallucinations, delirium, extreme agitation and psychosis).
• Funada et al (2002) found tolerance to locomotor-suppressant effects in mice.

Question 27

How was GHB first discovered and used?

Answer 27

• Discovered when looking for a GABA analogue to use as a CNS depressant for use as a sedative or anaesthetic.
• Initially sold in US health shops as a supplement for body builders to reduce fat and increase muscle, but adverse effects = ban.

Question 28

What are the behavioural effects of GHB in lab animals?

Answer 28

• Lower doses - sedation, reduced locomotor activity, decreased anxiety.
• Higher doses - cataplexy and CNS excitation (like petit mal seizures in humans?)

Question 29

Why do people take GHB?

Answer 29

Because of its reinforcing effect (although animal studies inconsistent): Funada et al (1992) place conditioning task in rats and mice showed reinforcing effect, but IV self-administration in monkeys didn’t. Some sedated themselves (either unpleasant or too drowsy to get more?).

Question 30

What are the different (vague!) hypotheses as to the neural effects of GHB?

Answer 30

1. Acts (weakly) on GABAB receptors/is metabolised into GABA.
2. There’s a GHB receptor - selective binding sites, GHB analogue selective antagonist.

Question 31

What is the evidence for and against GHB acting on GABAB receptors?

Answer 31

• Has little effect on GABAA receptors.

+ GHB effects counteracted by GABAB antagonists (Carter et al, 2003).

Question 32

What is the evidence for and against GHB being a neurotransmitter with its own receptors?

Answer 32

+ GHB = nt synthesised from GABA
- Endogenous GHB levels not behaviourally effective = different mechanism
- Not all GHB effects blocked by antagonist.
+/-/? At high doses GHB receptor antagonist acts like an agonist.