Pharmacology

  1. Definition of Pain
    • has a sensory and emotional component, very hard to explain to a person who hasnt felt it before and its a complex, and subjective experience.
    • overall pain is undertreated! common reason for a doctors visit. Many will ignore many things but when they are in pain it FORCES them to come in.
  2. Nociception
    pain perception by CNS, involves tissue damage, radiating pain can be felt, you can feel the pain, this is a normal signal process. Nervous system is working normally and activated
  3. Transduction
    where the pain starts. it is the process of converting the "stimulus" (smashed finger, burned finger) into a pain impulse.

    NSAIDS, Local Anesthetic work
  4. Transmission
    nerve impulses generated by stimulus travel up the spinal cord and are transmitted to the brain via NT

    Opioids, GABA analogs (baclofen) (gabapentin)
  5. Perception
    from the brain the impulses stimulate another area such as: thalamus, contralateral (opposite side) somatosensory cortex and limbic system

    information is perceived or interpreted by location, intensity and quality

    General Anesthetics
  6. Modulation of Pain
    attenuate pain or "lessen" it, by inhibitory input from brain (endorphins, NE, GABA)

    Opioids, SSRI's, TCA's, gabapentin
  7. Neuropathic Pain
    Nervous System/sensing is damaged and is NOT functioning normally. central or peripheral. Burning, tingling, shooting, numbness. Ex. diabetes neuopathy, shingles started with an infection even after it heals the pain can still be there.
  8. Acute Pain
    due to tissue trauma, will go away when situation resolves. Labor, cut
  9. Chronic Pain
    • Old Definition: 3-6 months beyond onset
    • New Definition: pain that serves no adaptive purpose and disrupts sleep and normal living

    can be nociceptive or neuropathic or BOTH
  10. Malignant Pain
    Pain related to cancer, we can determine cause of why in pain
  11. Chronic Nonmalignant Pain
    persistent pain that is not associated with cancer, pain itself is considered the disease. The pain consumes the patient. There is no apparent cause
  12. Tolerance
    body adapts to a drugs effects which results in needing more drug, Exposure of the drug results in changes or a lessening of one of the drugs affects. Can build up a tolerance of the drugs side effects or to the drug itself. = we need more.
  13. Physical Dependence
    when you take a drug away they have a withdrawl sx
  14. Addiction
    addictive behaviors, compulsive use, craving, breaking law to get drug, pyschological, out of control
  15. 5th vital sign
    pain, its a self/subjective report, personalized. Go with what the patient SAYS
  16. Non Opioids
    • used for acute: mild-moderate pain
    • APAP, NSAIDs,
    • non-selective: ibuprofen (Motrin)
    • selective cox 2 Celeboxib (Celebrex)
  17. Acetaminophen
    APAP, Tylenol

    • Usually used in combination with things:
    • Ex. Tylenol PM has benedryl w/ it
    • Tylenol #3 has codeine with it.
    • Lortab & Davocet N 100 has an opioid with it
    • Ultracet=APAP + tramadol
  18. Acetaminophen/Tylenol MOA:
    • centrally acting (analgesic) or pain reliever
    • blocks pain by inhibiting prostaglandin synthesis in CNS
    • lowers fever by hypothalamus (antipyretic effect)

    • usually takes 30 minutes-1hr
    • NO ANTI INFLAMMATORY EFFECTS
  19. APAP Toxicity
    • 2-500mg q 8 hrs = 4g total, maximum (limit)
    • ingesting 10-15 grams results in severe hepatotoxicity (liver)
    • if your a EtOH drinker or have liver problems you max intake of APAP per day is <2 g in 24 hour period
  20. NSAIDs MOA
    blocks the enzyme cyclooxygenase (COX) which inhibits prostaglandin synthesis and has anti platelet effects by blocking thyroxane

    • anti-pyretic effects
    • anti-inflammatory effects

    S/E: GI ulcer, prolonged bleeding
  21. Tramadol (Ultram) Middle step. Non opiod but his is a opiod wantabe! Quasi-opioid. Ultram is not a controlled substance in IDAHO!
    MIDDLE GUY: drug of choice for doctors who have pts where Ibuprofen and tylenol not enough but they dont want to rx Lortab or Vicodin

    moderate pain, works by a "dual" or two ways to help with pain. Weakly binds to (mu) opiod receptors AND inhibits uptake of NE and serotonin

    S/E: GI upset, drowsiness, enhance seizures by (lowering seizure threshold), diaphoresis
  22. When we take the drug away after pt has been on it for a while=this symptom or responce
    withdrawl. Can also get this affect if you give an antagonist cuz it "plugs" up all the receptors that you were using when you were orinally taking the drug for.
  23. "CET"S if you see this in a drug name then it has...
    • has tylenol in it
    • Ultracet, Darvocet
  24. Natural, synthetic or semi-synthetic drug class that has 3 major uses.
    • Opioids. 1.Analgesia-pain relief, 2. Antitussive-cough suppressant, 3. Antidiarrheal-slows gut motility
    • Derived from: Poppyplant, Morphine was 1st prototype
  25. OPIOIDS aka..............one to use if you want to be pharmalogically correct!!
    Opiates: morphine like, "naturally" derived,

    Narcotic drugs/Narcotics: (slang) morphine like with both analgesic and sedative properties. Carries a connotation of bad or negative! Lunesta commercials specifically state this is a NON NARCOTIC drug. Makes it okay to take.

    OPIOID: refers to the morphine like drug and refers to both natural AND synthetic compounds
  26. OPIOID Agonist MOA:
    binds at opiod receptors in CNS and GI tract. Once bound the "transmission" is inhibited or stopped from the periphery to the spinal cord by activation of the inhibitory or modulation pathway such as GABA, NE which slows down or inactivates that nerve impulse. So we get a relief from the somatic sensation of pain. or feeling of... physical pain. Also alterations of the limbic system occur=happy, feel good, euphoria
  27. Opioid Receptor Subtypes
    • 1. (Mu) opioid receptor: this is the one we are really targeting when we want to get people out of pain! S/E: inhibit slow RR and inhibit slow GI
    • 2. Delta:
    • 3. Kappa:
  28. moderate-severe pain, most effective pain reliever. Physician has to do a COMPLETE pain assessment. What have they tried in past? What worked, What didnt work ect.......
    Opioids for analgesia (pain)
  29. Opioids for cough
    antitussive effect attained with a lower dose then required for the analgesic effect. Not need as much if your just trying to slow down the cough it will NOT completely STOP it.

    • Robutussin Dextromethorphan (DM)-OTC. lack of analgesic effects, less addictive and doesnt cause as much constipation.
    • Usually combined with guaifenesin which "liquifies" the mucous to it comes/coughs up easier. Hopefully every cough you do have should be a productive cough.
    • Dont use OPIOIDS in kids<6 (cough syrups)
    • Codeine: S/E constipation
    • hydrocodone: S/E constipation
  30. Opioids for Diarrhea
    specific GI effects. reduce peristaltic effects, increase water absorption and alleviate diarrhea. Dont have CNS affects. These special opioids target the GI receptors

    • Immodium AD: Loperamide, OTC
    • Lomotil: Diphenoxylate, RX
  31. OPIOIDS effects on body systems
    • 1. CNS: analgesia, euphoria, sedation, decrease RR, cough suppression, miosis, nausea, temp (raise, decrease)
    • 2. Cardiovascular: bradycardia, hypotension, intracranial pressure
    • 3. GI: decrease peristalsis, constipation,
    • 4. Renal: anti-diuretic effect
    • 5. GU: reduced uterine tone, prolonged/slows down labor (ex. Nubane)
  32. Nubane is an opioid used during labor for......
    pain but the S/E is slowing of uterus or uterine contractions
  33. S/E of Opioids:
    1. Euphoria, 2. Sedation, 3. RR decrease, 4. Miosis (constriction of pupils), 5. N&V, 6. Constipation, 7. Pruritis (itching)

    A tolerance can build up to most SE but not all with continued use
  34. Euphoria, SE of opioids
    pleasant, floating sensation, feels good! Does not automatically mean addiction! Tolerance will develop. Dysphoria (anxious, excited) is possible and is an idiosyncratic effect.
  35. Sedation; SE of Opioids
    drowsiness, mental "clouding", caution driving ect. reaction time is slowed. CNS depressing agent. Tolerance will occur.
  36. Respiratory Depression (turn breathing off), SE of Opioids
    most feared SE of opioids. Tolerance will build up!This is what will kill individuals in an overdose. Stages occur. You go to sleep, deep sleep, do not wake up due to respiratory arrest.
  37. Do Not crush Oxycontin tablets why?
    Especially to a opioid naive. All 12 hours of drug will be released at the same time!!!
  38. Miosis, SE of opioids
    constriciton, pinpoint pupils. NO TOLERANCE DEVELOPS!! Mediated by parasympathetic pathways. Take opioids for long time, miosis occurs. That is just how it is. Walk around all the time. Doesnt mean they are addicted.
  39. Nausea & Vomiting (N&V), S/E of Opioids
    opioids active the brainstems chemoreceptor trigger zone (CTZ). Which=N&V. Tolerance does occur. Can be minimized by taking with food and refraining from activity. Anti-emetic drugs are added to help.
  40. Constipation, SE of Opioids
    do not build up a tolerance! Long term opioid use require a bowl regimen which includes laxatives on a schedule. Such as Miralax. DO NOT use bulk forming laxatives like Metamucil. It can make it worse! Needs to be slow and controlled not just BAM WHAM!
  41. Pruritis (itching), SE of Opioids
    opioids can cause a itchy skin rxn. Fentanyl appears to be the one to grab if we have a patient who easily breaks out. Tx with antihistamines or tx with switching opioids. DONT know if it build up tolerance. Some do, Some dont!
  42. Opioid Classes
    • 1. Phenanthrenes
    • 2. Phenylheptylamines
    • 3. Phenylpiperidines
    • 4. Morphinana
    • 5. Benzomorphans
  43. Opiate 1st class: Phenanthrenes (morphine like, naural)
    • Strong: Schedule II
    • Morphine
    • Hydromorphone
    • Oxymorphone
    • Heroine (diacetylmorphine)

    • Moderate: Schedule II
    • Oxycodone
    • Hydrocodone
    • Codeine breaks or metabolizes into morphine

    • Agonist/Antagonist:
    • Nalbuphine
    • Buprenorphine
  44. Opioid 2nd Class: Phenylheptylamines
    • Strong:
    • Methadone

    • Weak:
    • Propoxyphene
  45. Opioid 3rd Class: Phenylpiperidines dont cross BBB, used for GI effects or lack of.
    • Strong:
    • Fentanyl
    • Meperidine

    • Weak:
    • Diphenoxylate
    • Loperamide
  46. Opioids forms
    • Rectal suppositories (morphine, hydromorphone)
    • Transdermal Patch (fentanyl)
    • Intranasal Spray (butorphanol)
    • Buccal Lozenge (fentanyl)
    • Pt. controlled button:
Author
Nursing
ID
64741
Card Set
Pharmacology
Description
Pharmacology Pain Management
Updated