CLASP Flashcards
What are some of the key facts about methanol?
- toxic
- can be home a side product of home brew
- in anti-freeze
- can cause renal failure or blindness
- metabolised to formaldehyde then to formic acid
- treat poisoning with ethanol
What are some of the key facts about ethanol?
- rate of drunkness is proportional to lean muscle mass
- is absorbed in the small bowel
- women have less alcohol dehydrogenase
- spirits irritate gastric mucosa
What is the ethanol metabolism chemical pathway?
Ethanol——-alcohol dehydrogenase—–>acetaldehyde
Acetaldehyde——aldehyde dehydrogenase—–>acetate
Where is most of the alcohol metabolised?
the liver (90%)
At what numerical rate is the alcohol removed from the liver?
15mg/100ml/hour
What does decreased aldehyde dehydrogenase cause and how can this be used?
- decreased aldehyde dehydrogenase means increased aldehyde ====nausea
- a drug called Antabuse can decrease activity of aldehyde dehydrogenase so alcoholics will not want to drink alcohol
What effect does alcohol have on water and ADH?
- inhibits ADH
- less water reabsorption
- clearer urine
What effect does alcohol have on the heart?
- decreased heart force (-ve inotrope)
- increased HR to maintain CO
What heart condition can binge drinking cause?
SVT (ie holiday heart)
What are hangover headaches caused by?
- dehydration
- acetic acid
- serotonin
- other substances known as congeners
What is the medical name for hangover headaches?
veisalgia cephalgia
What two changes will be seen on a blood test that suggest alcoholism?
- high gGT
- abnormal clotting
What is hazardous drinking?
level of alcohol that increases the risk of harmful consequences (<35u for w, <50u for m)
What is harmful drinking?
causes mental/ physical damage (>35u for w, >50u for m)
What are the features of alcohol dependence?
strong desire to drink
difficulties controlling the use of alcohol
What are some of the assessments of alcohol dependence?
- DSM-5 = alcohol use disorder from mild to severe
- DSM-4 = alcohol abuse and dependence
- CIWA-AR = used for alcohol withdrawal
- AUDIT by WHO
- Severity of alcohol dependence questionnaire
What is the drug used for withdrawal and what are the possible side effects?
- Chlordiazepoxide
side effects= relapse, withdrawal worsening, cognitive issues, seizure etc
What are the other drugs that can be used for alcohol dependence?
- Acamprosate (decrease cravings)
- Naltrexone (decrease desire for alcohol)
- Disulfiram (aversion therapy)
- Nalmefene (opioid antagonist)
What does alcohol act as biochemically?
- postive allosteric modulator
- at the GABAa receptors which causes the channel to be kept open which in turn causes inhibition of neural firing
What does alcohol cause the release of?
dopamine which causes rewarding effects
What is the mesocorticolimbic pathway?
- ethanol binds to GABAa
- decreased cell firing by increase in GABAa activity
- decreased glutamate receptor activity
- decreased GABA release
- decreased inhibition
- increased firing of different neurone
- dopamine made
What effect does alcohol have on GABA and its release of molecules?
- w/out ethanol GABA is released so there is inhibition via Cl- channels
- w/ ethanol the channels open so there is MORE inhibition
What does chronic consumption of alcohol do to GABA?
the receptors internalise and when there is no ethanol, there is increased likelihood of seizures
What drug is used to decrease seizure possibility?
Lorazepam which replaces the action of ethanol so decreases the likelihood of seizures
