1. Pain Most common reason people seek health care Tissue damage activates free nerve endings (pain receptors) Generally indicates tissue damage

2. Bradykinin Strongest pain producing substances Strongest pain producing substances May be involved in acute pain May be involved in acute pain Prostglandins increase sensitivity to pain Prostglandins increase sensitivity to pain Chemical mediators activate and sensitize pain receptors or stimulate the release of pain producing substances Chemical mediators activate and sensitize pain receptors or stimulate the release of pain producing substances

4. Endogenous Analgesia Activated by nerve signals or by morphine- like substances entering the brain Activated by nerve signals or by morphine- like substances entering the brain Opiate receptors Opiate receptors Endogenous peptides Endogenous peptides

5. Opiod Analgesics Moderate to severe pain Moderate to severe pain Reduction of pain sensation Reduction of pain sensation Sedation Sedation Decreases emotional upset Decreases emotional upset Most are schedule II Most are schedule II

6. Opioid Analgesics Oral, IM, SQ, & IV Oral, IM, SQ, & IV PO requires high doses PO requires high doses Prevent or relieve acute or chronic pain (pg 73) Prevent or relieve acute or chronic pain (pg 73) Bind to opioid receptors in the brain and spinal cord and activate the endogenous system Bind to opioid receptors in the brain and spinal cord and activate the endogenous system

7. Clinical Uses Pg 74

8. Agonist-binds to a receptor site and causes a response Agonist-binds to a receptor site and causes a response Partial agonist-binds to a receptor and causes only limited actions Partial agonist-binds to a receptor and causes only limited actions Antagonist-bind to a receptor and produce no response Antagonist-bind to a receptor and produce no response

9. Agonists Prototype: Morphine Sulfate Morphine and morphine like drugs Morphine and morphine like drugs Activity at Mu, Kappa, & ??? Delta receptors Activity at Mu, Kappa, & ??? Delta receptors Severe & Chronic Pain Severe & Chronic Pain IV, IM, SQ, Suppository, Epidural,&, PO IV, IM, SQ, Suppository, Epidural,&, PO Impaired kidney function may cause prolonged drug action and accumulation Impaired kidney function may cause prolonged drug action and accumulation Nonceiling drug Nonceiling drug

10. Prototype: Codeine PO onset 15-30 minutes duration 4-6 hours Naturally occurring opium alkaloid Antitussive Analgesic Milder adverse effects than morphine May be combined with Acetaminophen

11. Contraindications Respiratory depression Respiratory depression Chronic lung disease Chronic lung disease Liver or kidney disease Liver or kidney disease Prostatic hypertrophy Prostatic hypertrophy Increased ICP Increased ICP

12. Agonist/Antagonist Prototype: Nalbuphine (Nubain) Agonist activity at some sites and antagonist at others Agonist activity at some sites and antagonist at others Low abuse potential Low abuse potential Potent analgesics Potent analgesics May produce withdrawal symptoms in those with opiate dependence May produce withdrawal symptoms in those with opiate dependence Synthetic Synthetic

13. Opioid Antagonist Prototype: Naloxone (Narcan) Reverse or block analgesia, respiratory depression Reverse or block analgesia, respiratory depression Onset within minutes and last 1-2 hours Onset within minutes and last 1-2 hours Shorter duration than opioids Shorter duration than opioids May give repeated injections May give repeated injections

15. Withdrawal Anxiety, aggressiveness, restlessness, lacrimation, rhinorhea, perspiration, pupil dilation, piloerection, elevated body temp, diarrhea, BP Anxiety, aggressiveness, restlessness, lacrimation, rhinorhea, perspiration, pupil dilation, piloerection, elevated body temp, diarrhea, BP Begin within few hours of last dose Begin within few hours of last dose Early recognition and treatment key Early recognition and treatment key

16. Side Effects & Assessments Respiratory depression Respiratory depression Hypotension Hypotension N & V N & V Constipation Constipation Monitor respirations Orthostatic pressures BP Bowel regimen

17. Teaching No Etoh Do not increase dose Stay in bed 30-60 minutes after receiving No heavy machinery High fiber foods & increase fluids

18. Non Opioid Analgesics Analgesic, Antipyretic, & Anti-inflammatory Drugs Acetylsalic Acid (Aspirin) Acetylsalic Acid (Aspirin) Acetominophen (Tylenol) Acetominophen (Tylenol) Ibuprofen (Motrin) Ibuprofen (Motrin)

19. Prototype ASA (Aspirin) Inhibits the synthesis of prostaglandins Inhibits the synthesis of prostaglandins Non selective COX inhibitor Non selective COX inhibitor Antiplatelet and Antipyretic Antiplatelet and Antipyretic Prevent sensitization of pain receptors to various chemical substances Prevent sensitization of pain receptors to various chemical substances

20. Contraindications PUD PUD GI or other bleeding disorders GI or other bleeding disorders Hypersensitivity Hypersensitivity Impaired renal function Impaired renal function Children with viral infections Children with viral infections

21. Prototype Acetominophen Does not cause N & V or GI bleeding Does not cause N & V or GI bleeding Does not interfere with clotting Does not interfere with clotting Lacks anti-inflammatory activity Lacks anti-inflammatory activity Metabolized in liver Metabolized in liver

22. Prototype Ibuprofen (Motrin) Anti-inflammatory agent Anti-inflammatory agent OTC OTC May be better tolerated than aspirin but work in a similar fashion May be better tolerated than aspirin but work in a similar fashion Hypersensitivity may occur in people with allergy to aspirin Hypersensitivity may occur in people with allergy to aspirin Contraindications similar to ASA (except Reye’s) Contraindications similar to ASA (except Reye’s)

23. Selective COX-2 Inhibitor Prototype: Celecoxib (Celebrex) Designed to relieve pain, fever, and inflammation Designed to relieve pain, fever, and inflammation Fewer side effects than older NSAIDS Fewer side effects than older NSAIDS Contraindicated with ulcers, GI bleeds, asthma, severe renal impairment, & allergy to other NSAIDS Contraindicated with ulcers, GI bleeds, asthma, severe renal impairment, & allergy to other NSAIDS

24. Mucolytic Prototype: Acetylcysteine (Mucomyst) Antidote to Acetaminophen overdose Antidote to Acetaminophen overdose Give PO Give PO Must be given within 24 hours Must be given within 24 hours Bad smell Bad smell

25. Activated Charcoal May be given for an overdose of Acetaminophen