Cocaine & Amphetamines Cocaine – Background Info From the leaves of Erythroxylan coca Ancient use in S. America Religious, Social, Euphoriant, and Medicinal Active alkaloid 1st purified from the leaves in 1860 – What we commonly know as Cocaine. Early Years Proven to be one of the 1st local anesthetics for surgery Sigmund Freud obtained and studied cocaine’s psychological effects Advocated its use and prescribed cocaine for depression and chronic fatigue. Later he realized its adverse side effects Early Years Cont. Cocaine incorporated into numerous medicines and beverages Coca-Cola Harrison Narcotic Act banned its use in 1914 Recreational use increased dramatically in the late 1960’s Inexpensive “crack” cocaine use spread in the late 1970’s Statistics In 1985 – Estimated 5.7 million users In 1997 – Estimated 1.5 million users Use in high schools increasing Forms of Cocaine E. coca contains about 0.5-1.0% cocaine Leaves are soaked in kerosene and gasoline and mashed Cocaine extracted in the form of coca paste Paste approx 50-60% purity Cocaine Hydrochloride Paste is treated with numerous chemicals to oxidize and purify the paste to form the water soluble cocaine hydrochloride powder. Can be close to 100% pure Can be injected, inhaled as powder, or ingested orally Cannot be smoked Freebase Form A.k.a. Crack Cocaine Similar to the unpurified insoluble coca paste. Made by reversing the oxidation process Cannot be inhaled (as powder) or injected because it is not water soluble Forms a stable vapor when heated and inhaled (smoked) Pharmacokinetics Absorption (Cocaine HCl) Absorbed from all sites of application Mucous membranes, lungs, stomach Vasoconstrictor crosses mucosal membrane poorly Plasma levels peak 30-60 minutes Nasal Inhalation causes slow absorption which allows for prolonged euphoric effect Pharmacokinetics IV injection Bypasses all barriers to absorption Total dosage goes into blood stream and eventually the brain Smoking Cocaine Base Absorption is rapid and complete at the lungs Effects onset in seconds, peaks in 5 minutes and lasts about 30 minutes Pharmacokinetics Distribution Penetrates brain rapidly Brain concentrations far exceed plasma levels Freely crosses the placental barrier Pharmacokinetics Metabolism & Excretion Half-life 30-90 min. Metabolized by enzymes in both plasma and liver Slowly removed from brain Positive urine tests for 12 hours Major metabolite is benzoylecognine Use With Alcohol In the presence of ethanol a different metabolite is produced – cocaethylene Cocaethylene has the same physiological effect on the brain as cocaine but more toxic Euphoric effects last longer Increases risk of dual dependency Increases severity of withdrawal Alcohol/Cocaine is the largest two drug combination resulting in death Mechanism of Action Dopaminergic Actions Potentiates the synaptic actions of dopamine, norepinephrine and serotonin Cocaine attaches to and blocks presynaptic dopamine reuptake transport proteins Dopamine stays in the synapse longer Mechanism of Action Behavior-reinforcing properties Dopamine is the key NT for reinforcement Studies show cocaine increases sensitivity of D3 dopamine receptors in nucleus accumbens and other parts of the mesolimbic system important for behavior reinforcment. Increased density of D3 receptors in OD victims Responsible for craving Effects of Short Term Use Low dose, nontoxic physiological responses include Increased alertness Motor hyperactivity Tachycardia Pupillary dilation Increased glucose availability Shifts of blood flow from internal organs to muscles Effects of Short Term Use Psychological Effects Immediate euporia Giddiness Enhanced self-consciousness Forceful boastfulness These last approx 30 min. Effects of Short Term Use Moderate euphoria lasts for 60-90 min A state of anxiety lasts for hours Thoughts race, rapid speech Sleep delayed Appetite suppressed A depressive state follows Effects of Short Term Use Effects in the CNS Depletion of Oxygen Cerebral Atrophy Seizures Others Numerous cardiovascular complications can occur with prolonged or single use Toxic and Psychotic Effects of Long-Term, High Dose Use Anxiety and sleep deprivation increase Hypervigilance Suspiciousness, paranoia, and persecutory fears Toxic Paranoid Psychosis Altered perception of reality that can result in aggressive or homicidal actions as a response to imagined persecution Medical Complications Many cardiovascular effects Heart attacks Irregular heart rhythm Respiratory failure Seizures Tolerance and Sensitization Tolerance to the “high” often occurs due to downregulation Sensitization of the anesthetic and convulsant effects occurs Explains some deaths occurring after low doses Comorbidity Chronic cocaine use produces virtually every psychiatric syndrome 300 abusers 56% met current criteria 73% met lifetime criteria Alcoholism and Heroin addiction extremely high in cocaine users Cocaine and Pregnancy Many indirect effects from the vasoconstriction of mothers blood vessels Decreased blood flow and oxygen to Uterus Associated with Placental detachment Preterm labor Stillbirth Low birth weight Others Cocaine and Pregnancy Direct effects from cocaine in the fetus Neonatal neurological syndrome Abnormal sleep patterns, tremors, seizures Increased incidence of SIDS Cocaine impaired children show difficulty developing attachments, dealing with multiple stimuli, aggression High incidence of ADHD Treatment There is no consensus on a generally accepted successful pharmacological treatment. Three problems that complicate therapy 1. 2. 3. Intensity of the drug effect and reinforcing action Pronounced tendency toward relapse Most addicts have a coexisting disorder Treatment Three areas of need for pharmacologic intervention 1. 2. 3. Antiwithdrawal agents to restore the dopaminergic tone of the limbic system Anticraving agents that block limbic dopaminergic receptors Treatment of coexisting disorders Treatment Psychosocial treatment offers the most promise Cocaine Anonymous Individual/Group counseling Cognitive behavioral therapy Psychodynamic therapy Behavior Reinforcement strategies Amphetamines - Background Used for over 60 years therapeutically for numerous disorders Schizophrenia Addictions (morphine and nicotine) Head Injury Hypotension Severe hiccups Others Amphetamines - Background Used in WW II to fight fatigue and enhance performance Widespread abuse began in 1940’s with students and truck drivers to stay awake and increase alertness Were used as appetite suppressants Mechanism of Action All CNS effects caused by the release of newly synthesized NE and dopamine from presynaptic storage sites Behavioral stimulation and increased motor activity result from stimulation of dopamine receptors in the mesolimbic system Pharmacological Effects Physiological Effects Increased BP Decreased HR Increased alertness Psychomotor stimulant Loss of appetite Pharmacological Effects Psychological Effects Euphoria Excitement Mood elevation Increased motor/speech activity Feeling of power Pharmacological Effects More effects Task performance may improve Dexterity deteriorates Pharmacological Effects Metabolized in the liver Excreted through the urine Detectable for up to 48 hours Pharmacological Effects At moderate doses Respiratory stimulation Slight tremors Restlessness Greater increase in motor activity Insomnia Agitation Pharmacological Effects At high doses Repetitive purposeless acts Sudden outbursts of aggression/violence Paranoid delusions Severe anorexia Overall psychosis and abnormal mental conditions Amphetamine Psychosis: paranoid ideation Primarily with meth users Pharmacological Effects In addition to the direct effects of the drug…. Infections from neglected health care Poor eating habits Use of unsterile equipment Great deterioration in social, personal, occupational affairs Pharmacological Effects Long Term evidence shows... Psychometric deficits Poor academic performance Behavioral problems Cognitive slowing General maladjustment The effects on this list are permanent. Dependence and Tolerance Use becomes compulsive Drug strongly effects areas of brain associated with behavior reinforcement Physical dependence follows a classical conditioning model Withdrawal occurs but not as dramatic as with narcotics and barbiturates Symptoms opposite of drugs effects Dependence and Tolerance Tolerance develops rapidly Necessitates the need for markedly higher doses Tolerance to the euphoriant effects develops which causes prolonged binging ICE Freebase form of methamphetamine Extremely potent High is intense and long lasting Chronic use can result in serious psychiatric, cardiovascular, metabolic and neuromuscular changes ICE: Pharmacokinetics Smoking causes immediate absorption Biological half-life around 11 hours 60% metabolized in the liver after distribution to the brain 40% excreted unchanged ICE: Effects and Toxicity Effects similar to cocaine Potent psychomotor stimulants and positive reinforcers Repeated high doses associated with paranoid psychosis ICE: Effects and Toxicity Many permanent effects due to longlasting abnormal brain chemistries Can cause permanent alterations in… Sleep functions Sexual functions Mood (permanent depression) Schizophrenia Movement disorders ICE: Effects and Toxicity Abnormal brain chemistries Studies show reduced neuronal density in frontal lobe and basal ganglia in abstinent meth users. Other Behavioral Stimulants Ephedrine Methylphenidate (Ritalin) Ephedrine In the news recently Steve Bechler Increases NE in the synapse Increases BP Weight Loss Methylphenidate (Ritalin) Mechanism similar to cocaine Also studies show it increases dopamine like amphetamine Used for ADHD Can be taken IV with cocaine like rush