Pharmacology

exert a calming effect, CNS depressant, too much can = coma, work on GABA receptors in CNS

• reduce anxiety
• anterograde amnesia (little bit of amnesia like when have a colonoscopy)

produce drowsiness and encourage sleep,CNS depressant, too much can = coma, work on GABA receptors in CNS

higher doses induce sleep. dont use them longterm cuz it can jack your REM cycle up

• Sedation
• Hypnosis
• Anesthesia
• Coma

dose response scale, older ethanol or barbituates=easier to overdose=coma, Benzodiazepines are newer drugs and are harder to overdose or cause coma and overall safer. Takes more of it to cause overdose effect

is a major inhibitory NT. "inhibitory" means that it inhibits or calms or slows down

• GABA (a) receptors: ex. benzodiazepines
• GABA (b) receptors: ex. muscle relaxants, baclofen

benzo's, barbit's, all drugs bind to a different part of the GABA receptor thats why all the drugs have different effects because they bind to a different area of the receptor yet same receptor type

• these are rapidly absorbed from the GI tract.
• S/S: sedation, euphoria, slowed rxn time, impaired motor function, slurred speech, ataxia, emesis, stupor, coma, respiratory depression, death.

• Affects CNS:
• 1. inhibits the excitatory route(glutamate) and enhances the action of (GABA)
• 2. heart depression of contractility
• 3. smooth muscle vasodilation in the periphery

• "Clinical" Uses:
• 1. self tx of anxiety, depression, tremors

• 1. used as anxiolytics and hypnotics
• 2. enhance GABAergic activity
• 3. undergo hepatic metabolism differently in different patients depending on age

• PHASE I: oxidation
• , active metabolites
• PHASE II: conjugation

• Short/quick Acting:
• alprazolam (Zanex), in and out
• Intermediate Acting: 6-8hr lorazepam, clorazepam
• Long Acting: 10-12+ hrs, diazepapm, flurazepam, active metabolites

they were our precursors, old drug that were used before benzodiazapines were invented. They are no longer used as regularly.are longer acting and cause more effects on CNS

Will prescribe them for epilepsey (phenobarbitol)

• Heavily marketed: Ambien: Zolpidem, Sonata: Zafeplon, Lunesta: Szopiclone are commonly prescribed sleep aids
• newer drugs introduced in the last 10 years that bind to GABA at different site then the Benzo's.
• rapidly absorbed, few metabolites, and short half lives which make them GREAT!

• antagonist of benzo's and non-benzo's (sleeping pills). Flumazenil can be used for overdose mgnt. Dont use very often. Only if you mix alcohol and benzo's
• Doesnt Block actions of Ethanol or barbiturates

• used for sedation
• hypnosis
• anesthesia

• anticonvulsants
• muscle relaxants
• effects respiratory and cardiac systems

both benzo's and barb's inhibit spread of epiletive electrical activity

Ex. phenobarbitol, clonazepam, diazepam, lorazepam

• Diazepam, Clonazepam
• take to calm you down b4 you go to dentist, relax muscles

At high doses, can cause respiratory depression and circulatory collapse

like soma

• Schedule IV:
• Benzo's
• Barb's
• non Benzo's (sleeping pills) ie. Zolpidem, Ambien

• agonist at melatonin receptors
• used to reset sleep patterns
• doesnt affect GABA
• with longterm use can affect testosterone and prolactin levels
• not a controlled substance

• acts on serotonin and dopamine
• NO GABA
• Reduces anxiety w/o causing sedation
• doesnt work immediately used more longterm

• Antihistamines: Diphenhydramine (Benadryl), Promethazine (Phenergan)
• Anitdepressants: amitriptyline (Elavil), Trazodone (Desyrel), SSRI's Prozac, Zoloft
• Antipsychotics: quetiapine (seroquel)

• work via:
• 1.locally
• 2.centrally
• to relax muscles

• Types:
• Neuromuscular Blocking Agents
• Centrally Acting Relaxants
• Direct Acting Muscle Relaxant

"oniums" block action of Ach. Dont let Ach bind to nicotinic receptors. prevents depolarization & propagation of the action potential

succinylcholine is the only depolarizing drug on market and it causes too much depolarization. The constant depolarizing makes the muscle fiber resistant to Ach and wears it out to it stops working, its too tired

blocks Ach activity at motor end. Results in paralysis/paralized

• also used to stop people from sweating too much, used to stop spams, used in surgery and ICU
• surgical relaxant
• tracheal intubation
• conrol of ventilation
• tx of convulsions

unable to relax a certain limb, its stuck, cannot move it

weve all had a pulled muscle or muscle strain after a sports injury. Unable to relax the muscle and it hurts., tonic contraction of the muscle. Ex. chronic low back pain, neck strain

• MOA: decrease reflex activity in the spinal cord. Inhibit motor neuron excitability
• S/E: drowsiness, dizziness, ataxia: unbalanced walking, fatigue and muscle weakness

• Baclofen (Lioresal): blocks GABA receptors. Orally, intrathecal Pumps,
• Dantrolene (Dantrium): used for servere situations. we need to relax things immediatley. direct acting. directly inhibits skeletal muscle contraction. works DIRECTLY on the muscle cell. It impairs the release of calcium during excitation therefore relaxing the muscle.
• Tizanidine (Zanaflex): alpha-2 receptor adrenergic agonist, can be used for both muscle spasms and spasticity, MS, post CVA, spinal cord lesions. S/E: lowers BP

• MOA: less clear. Probably blocks interneuronal activity???
• carisoprodol (Soma), metabolized to a controlled substance. Seems like it has abuse potential but right now is is not a controlled substance. Abuse potentials!
• #1. Cyclobenzaprine (Flexeril) 5mg vs 10 mg story. drug companies and money. You only need 5mg to do the job. and dont cut the 10 mg tabs that went generic buy this 5mg brand only version. This drug chemically looks the same as antidepressant Amitriptyline....S/E: drowsiness
• Metaxalone (Skelaxin)
• Methocarbamol (Robaxin)
• Tizanindine (Zanaflex) used for spasticity also

work at motor end plate

work at spinal cord or brain stem

directly on skeletal muscle, stoping calcium release