Drug Addiction Flashcards
What is tolerance?
Loss of effect when taking the same dose, person increases dose to achieved desired effect
What is dependence?
Physiological and psychological need to keep using a drug
Why does dependence occur?
Physiological changes (alcohol)
Psychological factors (cravings and compulsions to the drug)
Why do you get withdrawal symptoms?
Physiological adaptions to the drug e.g. alcohol and benzodiazepines
What pathway is responsible for psychological addiction?
Mesolimbic pathway
What is the key neurotransmitter in the mesolimbic pathway?
Dopamine
What key structures are involved in the mesolimbic pathway?
Ventral tegmental area
Nucleus accumbens
Amygdala
Prefrontal cortex
How do addictive substances or behaviours activate the mesolimbic pathway?
Dopamine release in the pathway providing pleasurable reward
Repeated exposure to dopamine reduces number and sensitivity of receptors
Therefore stronger stimulus needed for same reward
Every day activities less rewarding, person seeks out the substance or behaviour to stimulate the reward pathway
Where are cues for substance of behaviour embedded?
Amygdala
What causes cravings?
Cues
People, events, places or objects can act as cues triggering a craving
What is a common trigger of a craving?
Stress
What do changes in the prefrontal cortex lead to?
Impaired function
What is the prefrontal cortex responsible for?
Executive functions
Give examples of executive function
Decision-making
Assessing risk
Impulse control
Complete the table
How is drug addiction managed?
MDT approach
Specialist drug and alcohol services available, usually with self-referral option
What does drug addiction management involve?
- Detoxification
- Medication (to help maintain abstinence)
- Psychological and behaviour therapies
- Ongoing support
What medication is used for opioid dependence?
Methadone (bind to opioid receptors)
Buprenorphine (bind to opioid receptors)
Naltrexone (prevents relapse)
What medication is used for nicotine dependence?
Nicotine replacement therapy (patches, gum or lozenges)
Bupropion
Varenicline
What do you give in acute heroin withdrawal?
Symptomatic treatment, dont give opioids
e.g. lofexidine (a2 agonist)
What is malingering?
Fabrication or exaggeration of physical or psychological symptoms for personal gain or relief from duty or work
What are the early signs of opiate withdrawal?
Early 12 hours
Rhinorrhoea
Sweaty clammy skin
Persistent yawning
Tachycardia
Restlessness
Dilated pupils
Lacrimation
Goosebumps
Late day 2-3
Nausea and vomiting
Diarrhoea
Insomnia
Abdominal cramps
Muscle pains
What should be done before starting a patient on methadone prescription?
- Check that they are being prescribed methadone
- Urine drug screen
- There’s time, more than 24 hours before withdrawal symptoms, so check
How is methadone administered?
Methadone titration
Initial 20mg dose
If withdrawal symptoms persist, give further 10mg after 2 hours
Give total from day before next morning
Do not give more than 60mg unless prescribed already
Why does methadone accumulate over the first few days of treatment?
Long half-life
What is the aim of methadone treatment?
Stabilisation rather than detox
What is buprenorphine?
Partial agonist
Must be in withdrawal to start
