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ADDICTION. What is and what isn’t. Leo Lanoie, MD, ASAM Cert. Addiction is not:. Tolerance Physiological Dependence Excessive use Stupid use Intoxication. Tolerance. Occurs with many drugs Means larger dose required to reach the desired effect Larger doses needed reach toxic effect
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ADDICTION What is and what isn’t Leo Lanoie, MD, ASAMCert
Addiction is not: • Tolerance • Physiological Dependence • Excessive use • Stupid use • Intoxication
Tolerance • Occurs with many drugs • Means larger dose required to reach the desired effect • Larger doses needed reach toxic effect • If often seen in addiction but can occur without addiction
Physiological Dependence • Occurs with many drugs • Patient experiences withdrawal if drug is discontinued abruptly • Occurs in addiction but can occur in many non addicted patients.
Withdrawal • Occurs only in physiologically dependent persons • Occurs when drug stopped abruptly • Symptoms usually the opposite of drug effect • May be life threatening
Life Threatening withdrawal occurs with 2 groups of addictive drugs. • Alcohol • Benzodiazepines
ADDICTION The Three C’s • COMPULSION - Differs from craving in that it is subconscious • Loss of CONTROL • Continued use despite negative CONSEQUENCES
ADDICTION The American Society of Addiction Medicine states that, “Addiction is a chronic relapsing disease.”
Why do Alcoholics drink?Why do Addict drug? To feel normal
Pathophysiology of Addiction • Anhedonia • Neuro-adaptation • Plasticity
What it takes to become addicted Biology Psychology Environment Addiction
The Pickle Line Once a pickle, you can never again be a cucumber
The Pickle Line Amount Abuse Dependence Time
PSEUDOADDICTION • Drug seeking behavior in person with inadequately treated severe (usually chronic) pain. • Falsely labeled addicts. • Treatment is adequate pain management. • Cause: Opiophobia among physicians
Amphetamine vs Methamphetamine CH3 CH3 2
Stimulant Like: • Cocaine • Amphetamine • Methylphenidate • Ephedrine • Phenylephrine • Adrenaline (fight or flight reaction)
Drug Tmax (H) T1/2 (H) pKa Amphetamine 2-4 7-34* 9.9 Cocaine 1 .75-1.5 Methamphetamine 1-3 6-15* 9.9 Methylphenidate 1-3 2.4-4.2 8.8 * urine pH dependent: the lower the pH the shorter the half life Pharmacokinetics of Oral Stimulants
Intoxication = High • Caused by presynaptic release of catecholamines (Dopamine, noradrenalin, adrenalin) • Fight or flight = vasoconstriction, tachycardia, lower seizure threshold, dilated pupils, sweating, lots of energy, no appetite. • Behavioral and psychological effects: Euphoria, decreased fatigue, paranoia, hallucinations, delusional thinking
Intoxication • Visual, auditory, somatosensory hallucinations occur but formication is typical of stimulant psychosis. • Psychosis should resolve in a few days. • Psychotic flashbacks reported up to two years after cessation of methamphetamine use • Severe intoxication can result in organic brain syndrome • Serotonin syndrome (Triad of behavioral & cognitive changes; autonomic instability; neuromuscular changes)
Sensitization & Tolerance • Sensitization – (kindling) once exposed to a low dose of drug the effect is reached with an even lower dose of drug. • Tolerance – chronic use of high doses = more and more drug needed to produce same effect.
Withdrawal - Crash • Depression, fatigue, anhedonia, anxiety, difficulty concentrated, intense drug craving, increased appetite and hypersomnolence. • Most symptoms resolve spontaneously in a few weeks • Craving may persist • No physical withdrawal in the opioid or alcohol sense
Persistent Abstinence Syndrome • Anhedonia (depression) that can last up to two years after stopping drug use. • Thought to be due to dopamine depletion • Newer antidepressants such as Effexor may be helpful • Tryptophan supplementation recommended by some psychiatrists.
Methamphamphtamineand Immunity • Methamphetamine interferes with normal cellular immune response. • In HIV positive patients, viral load will increase five fold when they use Methamphetamine and return to normal when they stop.
Crystal Meth and Sex • Methamphetamine use is associated with hypersexuality. • Dopamine release in Nucleus accumbens is what produces sexual pleasure. The more dopamine, the greater the pleasure. • Dopamine release is far greater with cocaine.
Crystal Meth and Sex • Methampethamine causes ED. • Viagra • Burgeoning HIV epidemic in certain populations
Treatment of Addiction What works and What doesn’t
Assess Readiness to Change • Precontemplative • Contemplative • Preparation • Action • Maintenance Prochaska and Diclementi Relapse
Non Pharmacological • Motivational Interviewing and Motivational Enhancement • Cognitive Behavioural Therapy • Insight based Psychotherapy not recommended until patient in stable recovery. • Twelve step programs very effective in motivated patients
Abstinence vs Harm Reduction Paradigm shift from: Recovery = Total abstinence to Recovery = full return of function
METHADONE ASSISTED RECOVERY Prince Albert Community Methadone Treatment Program
Methadone MaintenanceNot a new idea • Dr Marie Nyswander and Dr. Vincent Dole New York in 1967 • That program is still going though a number of the original patients have since died of cigarette related illness
METHADONE • Synthetic opioid • Physiological dependence risk high in that it exhibits: - Tolerance - Physical dependence (Withdrawal) • Slow onset of action - 30 minutes
METHADONE (Continued) • Long half-life -24 to 36 hours • No euphoria • Blocks (Mu) receptors if dosage adequate: - Brain becomes unresponsive to euphoric effect of other opioids - receptors may be involved in alcohol effect.
Receptor the surface of a brain cell Receptor
Receptor the surface of a brain cell Agonist eg heroine or methadone
Opiate Blockade Naloxone Opiate Receptor Methadone Dr. Ray Baker – used with permission
METHADONE (Continued) • Painkiller - effect lasts 6 to 8 hours • Overdoses lethal in non- tolerant persons • Long term use is safe • Safe in pregnancy
METHADONE (Continued) • Takes 4-6 weeks to reach steady state (stabilize) • Patients prone to “drug sickness” during this period. • Usual dose 60-120mg but may be much higher
Methadone 24 Hour Dose Response Heroin Normal Range Dose Response Subjective w/d Objective w/d Time 0 hrs. 24 hrs. Slide courtesy of Dr. J. Thomas Payte