THC Pharmacology Flashcards
What is the principle route of cannabis administration?
Smoking
What does blood concentration of THC depend on when smoking?
Number, duration and spacing of inhalations
Inhalation volume
When can THC be measured in blood after smoking?
Within seconds after the first inhalation
How does absorption and concentration of THC differ when taken orally?
Slower absorption and lower and delayed peak concentration
When does peak THC occur when eaten?
1-3 hours after administration
What is the volume of distribution of THC?
10 L per kilogram
Why is THC retained in fat?
Because it is highly lipid soluble
What is the half-life of THC?
Up to four days in chronic users
What contributes to THC’s long half-life
Slow release from fat
What active substance is THC metabolized to?
11-OH-THC
What is the typical concentration of 11-OH-THC?
10% of THC concentration
What is the major inactive metabolite of THC?
Carboxytetrahydrocannabinol THC-COOH
What causes blood concentration of THC to begin to decline?
This happens as a result of metabolism in the liver and accumulation in the body’s fat stores
Why is plasma levels of THC from oral use low and variable?
Probably due to degradation in the stomach and first pass metabolism
In the residual cannabis levels in blood, urine and oral fluid following heavy cannabis use paper, for how long was blood THC detectible
For up to seven days after admission
Does THC excrete well into oral fluid?
No
Why might individuals have oral fluid concentrations of THC that exceeded the cut off for short periods of time?
Due to residual deposits in the oral cavity
Give examples of physiological effects of THC [5)
Increased heart rate
Reddening of the eyes
Dry mouth
Increased appetite
Vasodilation
What is the most consistent finding in studies of acute cannabinoid exposure?
Memory impairment
Besides memory impairment, what are some other mentioned side effects of THC use
Deficits in verbal learning, attention, inhibitory control, and psycho motor function
Can passive inhalers of marijuana smoke be misjudged for cannabis use during a routine drug screening
No, because THC levels in the body due to passive inhalation, do not reach the cut off point
Can postmortem changes occur for THC
Yes
What does a positive urine screen result for THC indicate?
Prior exposure
What is a positive oral test result for THC indicate
Recent drug use
What is the standard blood plasma concentration ratio for THC?
0.55
What is not indicated in a THC test (four)
Route of administration
Amount of drug taken
When the drug was last taken
Any impairing effects
In what type of cases may you see the issue of timing of drug use versus effects of THC be explored
Criminal cases
Corners in quests
Civil cases
What is a long-term supervision order?
A sentencing off to extend the length of time that the correctional service of Canada will supervise and support an offender in the community
What are the typical requirements of a long-term supervision order?
Individual is required to abstain from the consumption of alcohol or other intoxicating substances
Or
The consumption of drugs except in accordance with a medical prescription
