SUBS Research Discussion 2

SUBS 606

Addictive Substances

Alcohol

Recent data suggests may interact with membrane receptors. Comment by Cagwin, Callie Lynne (Center for Curriculum Development): Should this say “…suggests alcohol may…”

· Also gates for GABA, ACh, 5-HT

· GABA—inhibitory; reinforces by changing “subjective state”

· ACh—controls neurotransmitter release; ETOH decreases Ach which produces hypnotic, depressant effects Comment by Cagwin, Callie Lynne (Center for Curriculum Development): Should this be ACh

· Probably increases DA—reward center pathways

· ETOH reduces 5-HT which may cause in fluid intake generally Comment by Cagwin, Callie Lynne (Center for Curriculum Development): Should this say “…may cause increase in fluid intake” or “…may cause decreases in fluid intake” or something else?

· 5-HT modulates DA (increases reinforcement)

Sedative-Hypnotics

Anxiolytics, barbiturates; often includes alcohol; CNS depressant—main difference is onset, intensity, duration

· Depresses both excitatory and& inhibitory function

· Increases GABA effects

· Barbiturates are “dinosaurs” replaced by benzodiazepines

· Effects similar to alcohol, but ETOH is more toxic

· Used therapeutically for treatment of anxiety, sleep disturbance, & and anticonvulsants Comment by Cagwin, Callie Lynne (Center for Curriculum Development): Should this be “as anticonvulsants” or is this used to treat anticonvulsants?

· Cross-tolerance & and snynergismsynergism/potentiation

· Anxiolytics (vs. barbiturates)—effects affectson limbic system without affecting reticular activating system (consciousness & and awareness) or cortex (thinking & and problem-solving)

· Have high therapeutic index—OD resulting in death is rare when taken alone

· Buspar—good alternative; lacks generalized CNS depressant effects; takes 1-–2 weeks for therapeutic effect; less drowsiness, fatigue, mental slowing; low abuse potential; doesn’t have synergistic effects with alcohol; reduced cross-tolerance

Caffeine

80% of U.S. adults report daily intake; most have moderate consumption, with 20% dosing enough for clinical symptoms; most widely used psychoactive agent in the world; occurs naturally, but is also added to hundreds of prescription drugs, OTC analgesics, and stimulant, diet, and& cold products

· Caffeinism—syndrome of acute or chronic overuse characterized by CNS effects of anxiety, psychomotor agitation, sleep disturbances, mood changes, and/or psychophysiological complaints

· “cChoosers” experience being energetic, contented, & and alert; “nonNon-choosers” describe anxiety, jitteriness, & and mood changes

· Increase in DA & and NE are secondary effects, but stimulate reward centers

· Tolerance does develop—pharmacologically, risk becomes high when intake exceeds 500mg/day

· Absorption is high, complete, & and rapid; promptly crosses blood-brain barrier

· Caffeine reduces “natural” sedative, anxiolytic, & and anticonvulsant actions; blocks “tranquilizing”

· effect of adenosine

· Caffeine may help with migraines due to constricting blood vessels in brain

· Increases heart rate and& contraction force; diuretic & and enhances gastric acid; can produce headache, heart pain, & and fast or irregular heartbeat; diarrhea

· Withdrawal begins 18-–24 hours after last dose; lasts about 1 week—headache, fatigue, drowsiness

· Increased caffeine intake is associated with eating disorders, panic disorder/attacks, and increased anxiolytic use/abuse

· The “caffeine-alcohol-tobacco” triad

·

Nicotine

25% of US adults smoke cigarettes; over the years, the education gap has been widening (1965: -35% college grads; 1990-: 13.5% college grads); education status has become the best SES predictor of smoking rates; rate of decline—H.S. dropouts (.20), H.S. grads (.48), some college (.81), college grads (.84)

· 20% of total deaths attributable to smoking (400,000)—cardiovascular disease, respiratory, lung & and other cancers; reduced fertility & and fetal growth, increased ectopic pregnancy & and spontaneous abortion; non-smokers exposed to similar risks through “second-hand” smoke

· Those who quit live longer, healthier; decline in health risk continues for 10-–15 years Comment by Cagwin, Callie Lynne (Center for Curriculum Development): Could the decline in health item be moved to a new bullet point? And, could “are” be added before “healthier”?

· Produces tolerance & and withdrawal—rapid absorption, quick delivery, short ½ half-life; readily absorbed

· Stimulating nicotinic receptors and nicotinic-cholinergic receptors lead to peripheral nervous system effects; probably lead to secondary effects on dopaminergic systems in the forebrain

· Concentration/attention enhancements occur in former & and deprived smokers, not in nonsmokers or non-abstinent smokers

· Involved with other addictions

Opiates

Used in pain relief, intestinal conditions, & and cough suppressant

Opioids &and receptors occur naturally in the brain

· Enkephalins—similar to morphine; more potent

· Endorphins

· Act as neurotransmitters or modulators of neural activity; act on 3 different opiate receptors

· Involved in pain perception

· Tolerance—repeated use decreases effect; cross-tolerance among opiates