Substance Misuse Flashcards
What is considered to be ‘high risk’ drinking?
> 35 units per week regularly
increased risk is from 15 units +
Does heroin have a long or short half-life? What is the significance of this?
Heroin has a short half-life which means it causes a quick high but doesn’t stay in the system for that long which leads to cravings
What volume of pure alcohol = 1 unit?
10ml pure ethanol = 1 unit
How are alcohol units worked out?
(% x volume ) / 10
The % is expressed as a decimal e.g 40% = 0.4
The volume is in mls
What different drink quantities = 1 unit? (how much beer/ wine etc…)
1 single measure of spirits
1/2 a pint of beer
1/2 a small glass of wine
What are the recommended alcohol guidelines?
<14 units a week spread over 3 days or more
What are some of the physical consequences of alcohol consumption?
Gastritis
Peptic ulcers
Mallory-Weiss tear
Oesophageal varices
Cirrhosis
What factors are suggestive of alcohol dependence syndrome?
Tolerance
Withdrawal
Strong desire/ compulsion to drink
Difficulty with control
Neglect of other pleasures and interests
Persistence of use despite evidence of harm
What effect does alcoholism have on MCV?
Alcoholism is the most common cause of raised MCV
What are some of the detection tools which are used for alcoholism?
AUDIT
CAGE
TWEK
FAST
Which alcohol detection tool is used to detect hazardous drinkers?
AUDIT
Which alcohol detection tool is used to screen for alcohol abuse and DEPENDENCE?
CAGE
Which alcohol detection tool is used to screen for alcohol problems in pregnant women?
TWEK
Which alcohol detection tool is best for A&E testing?
FAST
Which toxicology parameter is a useful indicator of liver injury?
GGT
How does alcohol affect NMDA ion channels?
Alcohol inhibits the action of excitatory NMDA glutamate controlled channels
Chronic alcohol use leads to up regulation of these receptors
How does alcohol affect GABA channels?
Alcohol potentiates the actions of GABA controlled ion channels
Chronic alcohol use leads to down regulation of these receptors
How does alcohol withdrawal affect glutamate and GABA activity?
Alcohol withdrawal leads to excess glutamate activity and reduced GABA activity
*CNS excitability and neurotoxicity
Which receptors does chronic alcohol use upregulate and downregulate?
Chronic alcohol use causes up regulation of NMDA glutamate channels and down regulation of GABA channels.
When do withdrawal symptoms peak?
At 24-48 hours
What are some of the symptoms of withdrawal?
Restlessness
Tremor
Sweating
Anxiety
N&V
Loss of appetite
Insomnia
What happens to HR and BP in withdrawal?
Tachycardia
Systolic hypotension
How does delirium tremens present?
Acute confusion, disorientation and agitation
Visual hallucinations
Paranoia
How is alcohol withdrawal managed?
Benzodiazepines (gradually reduce over 7 days or more)
Thiamine
Antiemetics, analgesia, hydration
What can be done as relapse prevention for alcoholics?
CBT
Family and couple therapy
12 step facilitation therapy e.g AA
Medications
What medications can be used for relapse prevention for alcoholics?
Disulfiram
Acamprostate
Naltrexone
Disulfiram can be used as relapse prevention from drinking, how does it work?
Inhibits acetaldehyde dehydrogenase causing an accumulation of acetaldehyde if alcohol is ingested - this is unpleasant for the patient so deters them from drinking
Acamprosate can be used as relapse prevention from drinking, how does it work?
Acts centrally on glutamate and GABA systems to reduce cravings
Naltrexone is first line for relapse prevention in alcoholics, how does it work?
Naltrexone is an opioid antagonist which reduces the rewards from alcohol
Where does heroin come from?
Heroin = diamorphine / diacetylmorphine
Poppy seeds!
What are the different ways in which heroin can be taken?
IV
Smoking
Suppository
Insufflation (snorting)
Ingestion
How does drug testing for heroin work? What is the metabolic pathway for heroin breakdown and what compound are you trying to detect?
The metabolic pathway =
Diacetylmorphine (heroin) - 6 mono acetyl morphine - morphine
If 6 mono-acetyl morphine is detected, the patient has taken heroin
If morphine only is detected, don’t know if the patient has taken morphine or heroin
What are some of the signs you would expect to see on examination in a patient who has taken heroin?
Reduced consciousness
Low respiratory rate (respiratory depression)
Hypotension and bradycardia
Pupillary constriction
Why does heroin cause euphoria?
Injecting heroin causes a release of histamine which is what is though to cause the feeling of euphoria
Why do patients who take heroin often have poor dentition?
Poor self care
Heroin has an analgesic effect so often aren’t aware of pain from dental problems such as abscesses
When do withdrawal symptoms from heroin typically occur?
After 6-8 hours
How often do regular heroin users tend to inject?
3x per day
What are some of the withdrawal symptoms from heroin?
Agitation
Diarrhoea
N&V
Joint pains
Yawning
Runny nose and watery eyes
What are some of the physical signs of heroin withdrawal that may be seen on examination?
Piloerection (hairs stand one end) and goosebumps
Tachycardia
Hypertension
Dilated pupils
Is heroin withdrawal dangerous?
No unlike alcohol withdrawal it is just very unpleasant
What are some of the complications of IV drug use?
Infections (local - cellulitis, abscess, necrotising fasciitis and distant - infective endocarditis and systemic - Hep and HIV)
DVT/ PE
Which drug is used to reverse the effects of opioid overdose?
Naloxone
Heroin causes psychosis and delirium. T/F
No!
Heroin doesn’t cause psychosis or delirium
Drug-induced psychosis is most often due to cannabis
What drugs are used for opiate substitution therapy?
Methadone
Buprenorphine
How do methadone and buprenorphine differ? (opiate substitution options)
Methadone is a long acting full agonist and is usually in liquid form
Buprenorphine is a long acting partial agonist which is usually taken as a tablet dissolved under the tongue
Which is usually the preferred management of opiate addiction?
Opiate substitution therapy
Opiate detoxification has a higher risk of overdose
Why is opiate detoxification associated with overdose?
Patients are no longer tolerant but still psychologically dependent so if they take the same dose of heroin as before they may overdose
What psychological interventions are options for opiate addiction?
CBT
Behavioural couples therapy
What is the triad of wernicke’s encephalopathy?
Confusion
Ataxia
Nystagmus
Wernicke’s can progress to Korsakoffs syndrome. What does this involve?
Inability to make new memories
Confabulation to fill in the gaps
What are lilliputian hallucinations and when do they occur?
Seeing little people/ animals
Occur in delirium tremens
