NARCOTIC & OPIOID
narke----any substance that relieved pain, dulled the
senses, or induced sleep.
Opiate receptors are distributed widely in the brain,
and are found in the spinal cord and digestive tract.
narcotic=substance that binds to opiate receptors or
pain will give release of opiates (endorphins and
Act like inhibitory transmitters… yields less pain.
opium poppy used by Egyptians,Greeks, Romans.
morphine=purified constituent of opium---Morpheus---Greek god of dreams….euphoria
MOA----these drugs interact with specific receptor sites and
have effect on CNS, acting on receptors located on
neuronal cell membranes. The presynaptic action of opioids to
inhibit neurotransmitter release is considered to be their
major effect in the nervous system. also acts on gut wall and
Even in therapeutic doses, narcotic analgesics can cause
respiratory depression, nausea, and drowsiness. Long
term administration produces tolerance, psychic, and
physical dependence called addiction. These drugs are
commonly prescribed to manage pain, but can also be
prescribed to treat diarrhea (Lomotil) or severe cough (codeine).
Narcotic agents may be classified into four categories:
1--Morphine and codeine-- natural alkaloids of opium.
2---Synthetic derivatives of morphine such as heroin.
3--- Synthetic agents which resemble the morphine
4---Narcotic antagonists which are used as antidotes
for overdoses of narcotic analgesics.
opioids --- bind to presynaptic nerve terminal calcium channels.
this shortens action potential and yields inhibitied
opioids---bind to postsynaptic receptors in ascending
pain pathway yields reduced action potential
opioids---cause increased transmission of the descending
inhibition of spinal nociceptive conduction.
Schedule II/III controlled drugs.
adverse reaction----respiratory depression, constipation,
confusion, naseau, euphoria
consider----addiction and tolerance. federal and state laws
for processing, dispensing, maintaining records.
examples-acet w codeine----tylenol w codeine
acet w hydrocodone----Lortab
acet w oxycodone----Percocet
acet w propoxyphene----Darvocet
Nonsteroidal Antiinflammatory Drugs:
prostaglandins have 20 carbon chain that includes
5 carbon ring.
Make a prostaglandin-------cell injury releases arachidonic acid.
cyclooxygenase will convert AA into PG. This irritates
nerve endings, yields pain and inflammation.
COX 1and COX2 hit different sites on AA.
COX1 makes PG for kidney function,stomach protection
mucous, blood clotting.
COX2 makes PG for pain,heat, swelling.
Most NSAID attack COX1 and COX2.