Introduction to Stimulants and Hypnotics Flashcards
Stimulant drugs definition and types
Stimulant Drugs: drugs that promote wakefulness
→ drugs that enhance NE/DA, modafinil (orexin enhancer), caffeine, nicotine
Ephedrine/pseudoepedrine
- source
- mechanism
- effects
- uses
Ephedrine/pseudoephedrine → NE receptor agonist
Source: ma huang shrub in chinese medicine (galenical), pure extract in 19th century
Mechanism: activates alpha and beta NE receptors, NO EFFECT on DA
Effects: mild euphoria (not extreme high as others), pressor effects (raises BP)
Uses
Ephedrine: stimulant - used to raise BP in surgery
Pseudoephedrine: decongestant - sold in cold medicine OTC (Sudafed)
Amphetamines
- source
- mechanism
- effects
- uses
- problems
- trade names
Source: pure synthetic - made from ephedrine since 1930s
Mechanism: releases NE and DA from the neurons into the synapse
Effects: wakefulness, euphoria, pressor, decreased appetite, dries nasal secretions
Uses: stimulant (ADHD, narcolepsy), recreationally (non medical), formerly used to dry nasal secretion and for weight loss
Problems: abuse liability and dependence
Trade names - benzedrine (amphetamine) and dexedrine (dextroamphetamine)
cocaine/methylphenidate
- source
- mechanism
- effects
- uses
- problems
- trade names
Source: cocaine from coca leaves, methylphenidate is a pure extract
Mechanism: blocks reuptake of DA and NE by inhibiting catecholamine transporters at presynaptic vesicles → increases levels in the synapse (topically blocks VDSCs)
Effects: euphoria, wakefulness, dries nasal, secretions suppresses appetite, pressor
Uses: cocaine → local anesthetic (VDSCs) and recreationally (NE/DA), methylphenidate → ADHD, narcolepsy (NE/DA)
Problems: dependence, weight loss, dry mouth, insomnia, schizophrenia (repeated high dose can present as schizophrenia and how we differentiate is with the peripheral effects of stimulants like high BP)
modafinil
- source
- mechanism
- effects
- uses
- problems
orexin enhancer
Source: synthetic, active metabolite of adrafinil (failed neurotropic)
Mechanism: Carlson suggests it enhances orexin (hypocretin) and histamine release, other sources say it blocks DA reuptake
There is no euphoria associated and no peripheral effects
Effects: wakefulness, MILD OR NO euphoria, no peripheral effects
Uses: ADHD, narcolepsy, shift work, sleep apnea
Problems: reported in less than 10% of people → headaches, insomnia
Caffeine and caffeine like drugs
- source
- mechanism
- effects
- uses
- problems
Caffeine and caffeine like drugs → adenosine receptor blockers
Source: galenicals - coffee, tea, cocoa, coca cola
Mechanism: blocks adenosine receptors which produce a sleep signal when adenosine binds to them (adenosine is formed by ATP use) (old view was that it blocks phosphodiesterase which increases cAMP)
Effects: wakefulness, mild to no euphoria
Uses: mild stimulant (world’s most used psychoactive drug)
Problems: raises BP, insomnia, GI upset, dependence
Stimulants used to treat narcolepsy
Narcolepsy: amphetamines, methylphenidate, modafinil
Stimulants used to treat ADHD
ADHD: amphetamines, methylphenidate, modafinil
Stimulants used to treat shift work and sleep apnea
Shift work and sleep apnea: modafinil
Stimulants used to combat fatigue
Combat fatigue: amphetamines, modafinil
Hypnotic drugs definitions and types
Hypnotic Drugs: drugs that promote sleep
→ enhances of the GABA-A system, orexin blocker (suvorexant), old antihistamines
Barbiturates
- source
- mechanism
- effects
- uses
- problems
- trade names
Barbiturates - enhancer of GABA → sedative/hypnotic/anesthetic
Source: pure synthetic - barbituric acid
Mechanism: bind on GABA-A related Cl channel as positive allosteric modulators → they increase the length of time that the channel is open (at low doses need GABA to open it but at high doses can do it themselves)
Effects: sedative, hypnotic, general anesthetic
Uses: phenobarbital used in epilepsy and general anesthesia in animals (used to be used for sedation and hypnosis and induction of anesthesia not anymore due to OD)
Problems: hangover, addiction, suicide
Examples: phenobarbital, bentobarbital, thiopental, methohexital → old drug for anesthesia
Benzodiazepines
- source
- mechanism
- effects
- uses
- problems
- trade names
Benzodiazepines - enhancer of GABA → sedative/hypnotic
Source: pure synthetic
Mechanism: bind to site on GABA-A related Cl channel, PAM → increases the affinity of GABA to the channel but can’t open it itself → no risk of OD (but mixing with alcohol or barbs can kill you)
Effects: anxiolytic, promotes sleep (doesn’t compel)
Uses: short term anxiety, hypnotic (temazepam), preanesthetic medication (midazolam)
Problems: sedation, dependence, no OD or suicide (but lethal with alcohol/barb)
Examples: diazepam, chlordiazepoxide, midazolam (presurgery)
Z-Drugs
- source
- mechanism
- effects
- uses
- problems
- trade names
Z-Drugs - enhancer of GABA → hypnotic
Source: pure synthetic
Mechanism: binds to benzo site on GABA-A related Cl channel (acts like benzo)
Effects: promotes sleep
Uses: hypnotic
Problems: dependence
Examples: zolpidem, zolpiclone, zaleplon
Suvorexant (Belsomtra)
- source
- mechanism
- effects
- uses
- problems
Suvorexant (Belsomra) - OREXIN ENHANCER → hypnotic
Source: pure synthetic
Mechanism: blocks orexin 1 and 2 receptors (but doesn’t induce narcolepsy which occurs when orexin receptors are blocked)
Effects: promotes sleep
Uses: hypnotic
Problems: dependence
