Recreational Drugs (GHB/GBL and Opioids) Flashcards
What are the acute effects of G?
1) Euphoria
2) Increased sexual arousal, stamina and pleasure
3) Reduced negative self-esteem
4) Altered perception of time
5) Impaired memory
6) Salivation → G dribble
7) Slouching and unsteadiness (G droop)
8) Loss of consciousness (coma)
What are the effects of G that can lead to death?
Bradycardia, hypotension, respiratory depression → death
What is GHB?
A GABA analogue that binds to pre-synaptic GABA receptors and decreases GABA release
What is the therapeutic index of G and why does this matter?
It has a v narrow therapeutic index (0.5ml) → therefore there is a v small gap between recreational and deadly dose
What is a normal dose of G?
1-2 ml
What is the half life of G and what does this mean?
It has a v short half life → so people often come round in a few hours
How do you care for someone who has G intoxication?
1) Supportive → oxygen, protect airway
2) Be alert to mixed intoxication with stimulants
3) Only intubate if vomiting, seizure or other indication, not unnecessarily
4) Don’t give naloxone unless unsure if have also taken opioids
What will be the difference if a G intoxicated patient has also taken stimulants (cocaine, methadone, methamphetamine)?
No hypotension or bradycardia
What are harm minimisation advice tips for G?
1) Use pre-measured doses
2) Avoid alcohol → increases risk of OD
3) Avoid stimulants → increases dosing
4) Watch friends for G dribble/slouch
5) Time doses at minimum 90-120min intervals
6) Test dose for new batch
7) Set limit for how much G in a day/how frequently you use G
8) Write G on wrist so paramedics know in emergency
9) Never use it to sleep
10) BBV checks (often used with meth), sexual health review
What levels of G use are associated with dependence?
> 15-20 ml a day or more than 2 days a week
What is G withdrawal like?
Like alcohol withdrawal but with more delirium, fewer seizures and quicker onset
What are symptoms of GBL dependence?
- Using every couple hours every day
- Using alcohol or BZDs to manage withdrawal symptoms
- Waking up at night to use
- Preoccupation
- Prioritising G over other things
What do you use to assess G withdrawal?
CWAS
How do you treat G withdrawal?
V aggressively → BZDs might not be able to manage behavioural disturbances
What are symptoms of G withdrawal?
1) Anxiety
2) Agitation
3) Sweating
4) Shaking
5) Increased HR
6) Increased BP
7) Visual and auditory hallucinations → more likely than with alcohol
8) Confusion
Describe the process of G detox
- Use CIWA to evaluate the withdrawal severity
- Some people work with a key worker and cut use down slowly and others need a planned detox
- If planned, give baclofen (GABA-B agonist) 10mg TDS for the week before then increase to 20mg TDS
- Once in withdrawal, add BZDs (diazepam/librium) → large doses and 10-14 days
- Check up every day, check not using G, rate symptoms, give as much BZDs as need for that day
- Give clear instructions to call ambulance if not going well/feeling confused (also need someone at home with them)
What are symptoms of opioid overdose?
1) Low BP and pulse
2) V low RR (8)
3) V low SpO2 e.g. 70% (basically not breathing)
4) Pin point pupils → v small but equal
5) V thin and track marks on arms
What do you give to someone who has had an opioid overdose?
Naloxone
By what routes can you give naloxone?
- IM over clothes into e.g. leg
- Intra-nasally if have it
- Difficult to give IV to IV drug user
Why do you have to careful not to give too much naloxone?
Bc can cause a crashing opioid withdrawal (v horrible) → might cause patient to panic and run off to reverse the withdrawal
How do you give naloxone?
Give half and then the other half if they still don’t come round → titrate dose against patient’s response
What should you do while giving naloxone?
- Talk and interact with patient and bc positive, reassuring and kind → bc it’s a brain stem effect, if you engage with them they talk and breathe when they come round which keeps them going
- Good, positive interaction where you explain what is going on and what you will do next reduces aggression
How long does naloxone last and what does this mean?
20 minutes (short acting) → so may need to give repeat dosing esp. if people are taking newer synthetic opioids like fentanyl
What should you do after giving one dose of naloxone?
Continue respiratory monitoring and support
What can happen as a result of giving naloxone?
People can become aggressive or go into withdrawal
How do opioids suppress respiration?
1) Opioids bind to mu opioid receptors in the respiratory centres of the brainstem (pons) and medulla and chemoreceptors
2) Stimulation of these receptors slows respiration and makes them less responsive to low oxygen and high CO2
What is important to remember about opioid overdose?
That it isn’t always an overdose
- Person might not have taken unusual amount for them
- Hypoxia and hypercapnia can occur at usual dose
What can increase risk of opioid overdose?
1) Medical co-morbidity e.g. COPD, chest infection
2) > 50
3) Prescribed or recreationally consumed sedatives e.g. alcohol, BZDs, pregabalin (interaction)
4) Contamination of opiates with e.g. fentanyl (change in potency)
5) Change in tolerance e.g. after prison release
What is important to remember about SpO2 in response to opioids?
Unpredictable → for one person a dose that is ok for most will cause a bit drop in SpO2 (so need to be careful when increasing diamorphine infusion)
What are the steps if you see someone with an opioid overdose?
1) Call 999
2) Give basic life support → CPR
3) Give 400 mcg naloxone injection into outer thigh or upper arm muscle
4) Give 3 cycles of BSL
5) Repeat giving naloxone and 3 cycles of life support until ambulance arrives or patient is breathing normally
What is involved in after care of a patient who has had an opioid overdose?
1) Make sure the person is shown how to use naloxone and given some
2) Organise an assessment at the local addiction team → substitution treatment saves lives
How does naloxone work?
- Antagonist → binds to receptor but has no action
- In the brain, it competes with the opioids for binding sites, blocking their action
- It has a high affinity for the mu opioid receptor
What is the problem with naloxone and what does this mean?
- It is rapidly redistributed from the brain
- Therefore, half life is 60-90 min → so need to observe and dose again
- Also, high affinity opioids e.g. fentanyl may need high and repeated doses
What drug do you need to be careful with prescribing to someone with opioid dependence?
Benzodiazepines
