Drug Abuse Flashcards
What is the key point to remember about drugs of abuse?
Not all people using a druse are abusing it, but all drugs do have an abusive tendency, some higher than others.
What is drug abuse?
Using a drug that outside its medically intended purpose.
What is the spectrum of drug abuse?
Casual/Non-probelmatic use - recreational and casual use
Chronic Dependence - use that has become habitual and compulsive. It can have negative health and social effects
Beneficial Use - Positive health, social, or spiritual effects. (Ex: coffee/tea)
Problematic use - use that begins to have negative consequences for an individual, family and society.
Ex: harmful routes of administration
What is dependence?
A physical dependence. The change in homeostasis of the body that occur after repeated administration. The body has to work harder to counterbalance the changes.
What are the steps?
Tolerance, Dependence, and Withdrawal
Is acquired tolerance permanent?
Though it is generally reversible, it is dependent on the removal of the drug and the restoration of underlying biology/physiology.
What are the kinds of tolerance?
innate tolerance –> tolerance that a general population is born with
acquired tolerance –> after repetitive drug use, an acquired tolerance forms
Why does tolerance pose such a risk?
Building tolerance means you will need a higher dosage in order to feel its effects. This increases its therapeutic index to a point where it may be lethal.
What is pharmacokinetic tolerance?
Reduction in drug plasma. Ex: ethanol induces enzymes that influence metabolism. This removes it from the system faster, hence reducing its response. This builds up the tolerance.
What is pharmacodynamic tolerance?
Occurs when you become essentially less sensitive to the drug.
Altered receptor expression - if the drug is always stimulated, the body can internalize receptors. By doing this, there is lower affinity and hence more drug is needed so it can bind.
Receptor desensitization - altered coupling between receptor and second messenger protein
What is withdrawal syndrome?
caused by a bodily imbalance following an abrupt cessation of drug until the drug free equilibria can be restored.
What happens when someone is going through withdrawal?
Sometimes hyper arousal of physiological systems can occur due to drug induced adaptions. The body reacts opposite as it would if it is on the drug. The severity is determined by the pharmacokinetics.
In what ways can withdrawal have more/less severe effects?
1) cold turkey drug cessation - withdrawal is the worst (naloxone and fentanyl)
2) less rapid drug free restoration
What is an example of a less rapid drug free restoration?
Methadone is a lipophilic drug used to help those struggling with abuse. Due to its lipophilic nature, it stays in the body (fats) for a long time. It takes a long time to be excreted and hence it is a good drug that helps the body adapt without the severe withdrawal effects.
What is addiction?
Progressive, out of control drug abuse that causes psychological dependence that can prevail long after successfully navigating dependence/withdrawal.
