5.12 pharmacotherapy of substance use disorders Flashcards
How does the DSM5 define substance use disorder?
Problematic pattern of substance use leading to clinically significant impairment or distress, with having two of the following occurring in a 12 month period:
- Taken in larger amounts; over a longer period than intended
- Persistent desire or unsuccessful efforts to control use
- Great deal of time spent in activities necessary to get substance or recover
- Craving, urge to use
- Recurrent use results in failure to fulfill major obligations
- Continued use despite social or interpersonal problems
- Continued use even though it’s hazardous
- Continued use despite realizing it’s harmful
- Tolerance
- Withdrawal
What is the presentation of having a BAC of 50 mg/dl (0.05 mg%)?
Motor function impairment observable
What is the presentation of having a BAC of 80 mg/dl (0.08 mg%)?
- Moderate impairment
- Legal definition of intoxication in most states
What is the presentation of having a BAC of 450 mg/dl?
Respiratory depression
What is the presentation of having a BAC of 500 mg/dl?
- LD50 for ethanol
- Lethal
What is the time of onset after withdrawal for alcohol withdrawal stage 1?
6-8h
What clinical features are present w alcohol withdrawal stage 1?
- Moderate autonomic hyperactivity (anxiety, tachycardia, nausea, insomnia)
- Craving for alcohol
What is the time of onset after withdrawal for alcohol withdrawal stage 2?
24h
What clinical features are present w alcohol withdrawal stage 2?
- Autonomic hyperactivity w auditory or visual hallucinations lasting 1-3 days
- Most remain lucid and oriented
What is the time of onset after withdrawal for alcohol withdrawal stage 3?
1-2 days
What clinical features are present with alcohol withdrawal stage 3?
4% of untreated pts develop grand mal seizures 7-48h after drop in BAC
What is the time of onset after withdrawal for alcohol withdrawal stage 4?
3-5 days
What clinical features are present w alcohol withdrawal stage 4?
Delirium tremens (DTs) in 5% of pts (confusion, illusions, hallucinations, agitation, tachycardia, hyperthermia)
What are risk factors for delirium tremens?
- Prior hx of DTs (#1 predictor of future DTs)
- # of detoxifications
- Consuming equivalent to 1pint of whiskey/day for 10-14 days prior to admission
- Early sxs of withdrawal
- Hepatic dysfxn
Pts w DTs can experience something called kindling. What is kindling?
Repeated withdrawal episodes increases the severity of subsequent withdrawal syndromes
What is the prophylaxis/fixed dosing tx of alcohol withdrawal?
- No liver dysfxn: diazepam, chlordiazepoxide, lorazepam, oxazepam
- W liver dysfxn: lorazepam, oxazepam
- May also use lorazepam PRN to supplement
What is the advantage of using a prophylaxis/fixed dosing tx for alcohol withdrawal?
Prevent withdrawal
What is the disadvantage of using a prophylaxis/fixed dosing tx for alcohol withdrawal?
Unnecessary BZD dosing
What is the individualized dosing tx of alcohol withdrawal?
- CIWA <8: Nonpharm tx
- CIWA 8-15: Medicate
- CIWA >15: Risk of complications if untx
- No liver dysfxn: diazepam, chlordiazepoxide, lorazepam, oxazepam
- W liver dysfxn: lorazepam, oxazepam
Should phenytoin be used for alcohol withdrawal?
- Takeaway: phenytoin doesn’t work
- Not effective to tx withdrawal seizures
What is always recommended if there is any suspicion of alcohol abuse?
Thiamine 100mg daily, usually duration of hospital stay –> reduce risk of Wernicke’s
What is Wernicke’s a result of?
Thiamine deficiency
When should thiamine be given?
Give before dextrose-containing fluids
Why is thiamine required to prevent Wernicke’s?
- Thiamine is a cofactor in glucose metabolism
- Wernicke’s can be precipitated by high glucose loads
