Why do ortho PTs need to know about pharmacology? Pharmacology for Orthopedic Physical Therapists. Pharmacology Defined: Pharmacology Defined:

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Pharmacology for Orthopedic Physical Therapists Julie DeVahl, PT, MS Assistant Professor Department of Physical Therapy Why do ortho PTs need to know about pharmacology?

1 Pharmacology for Orthopedic Physical Therapists Julie DeVahl, PT, MS Assistant Professor Department of Physical Therapy Why do ortho PTs need to know about pharmacology? Collaborative medical model Assist the patient, physician and pharmacist in the management of disease Evaluate effectiveness of PT interventions Pharmacology Defined: Pharmacology Defined: The study of how chemical substances affect living tissue, including how these agents bind to receptors to enhance or inhibit normal function. Gladson 2006 The study of drugs. Ciccone 2007 Any substance that, when taking into a living organism, may modify one or more of its functions. Pharmacotherapeutics Refers to the use of specific drugs to prevent, treat, or diagnose a disease. Pharmacokinetics: What the body does to the drug Pharmacodynamics: What the drug does to the body Pharmacokinetics Routes of Administration Enteral Oral Sublingual or buccal Rectal

Pharmacokinetics Routes of Administration Parenteral Inhalation Injection-

Topical Transdermal Pharmacokinetics Absorption Distribution Storage

drugs Implications of Pharmacokinetics Timing of rehab sessions Oral

absorption/distribution by heat, exercise and massage by cold Compliance

2 Pharmacokinetics Routes of Administration Parenteral Inhalation Injection- intervenous, intra-arterial, subcutaneous, intramuscular, intrathecal. Topical Transdermal Pharmacokinetics Absorption Distribution Storage Elimination Metabolism Excretion Pharmacokinetics Pharmacokinetics Half-life of drugs Implications of Pharmacokinetics Timing of rehab sessions Oral administration: minutes Consider effects of rehab on absorption/distribution by heat, exercise and massage by cold Compliance Implications of Pharmacokinetics Factors Influencing Biotransformation Genetic Physiological Environmental Recognize improper drug responses

A word on drug nomenclature Generic name is a short

issue Generics may be marketed by different trade

Name: ibuprofen Trade Names Pharmacodynamics Mode of

Anti-inflammatory 2. mild-moderate pain 3.

Anticoagulation - inhibit platelet aggregation Drugs

cellular cyclooxygenase (COX) prostaglandins

3 A word on drug nomenclature Generic name is a short version of the chemical name Trade name is a marketing issue Generics may be marketed by different trade names if the patent has expired (~20 years) Generic Name: ibuprofen Trade Names Pharmacodynamics Mode of Action Safety Profile Drugs (NSAIDs) 1. Anti-inflammatory 2. mild-moderate pain 3. Antipyresis - alleviate fever 4. Anticoagulation - inhibit platelet aggregation Drugs (NSAIDs) Modes of Action Inhibit the action of cellular cyclooxygenase (COX) prostaglandins thromboxane Drugs (NSAIDs) Aspirin (acetylsalicylic acid) Prototypical NSAID Used clinically for <100 years Inexpensive Readily available

Drugs (NSAIDs) adapted from Ciccone 2007 Drugs (NSAIDs) adapted from Ciccone 2007 Generic Name Trade Name Comments aspirin diclofenac Bayer, Bufferin, Ecotrin, St.

4 Drugs (NSAIDs) adapted from Ciccone 2007 Drugs (NSAIDs) adapted from Ciccone 2007 Generic Name Trade Name Comments aspirin diclofenac Bayer, Bufferin, Ecotrin, St.Joseph, Voltaren, etc Cataflam Most widely used NSAID for analgesic and anti-inflammatory effects More potent than naproxen; adverse side effects in 20% diflunisal Dolobid Potency 3-4x >aspirin etodolac Lodine As effective as most NSAIDS with fewer side effects fenoprofen Nalfon GI side effects common, but usually less intense than similar doses of aspirin Generic Name Trade Name Comments flurbiprofen Ansaid Similar to aspirin s benefits and side effects ibuprofen Motrin, Advil, Nuprin, Medipren 1 st non-aspirin NSAID also available in nonprescription form; GI side effects 5-15% indomethacin Indocin Relative high incidence of dose-related side effects: 25-50% ketoprofen Actron, Orudis Similar to aspirin benefits and side effects; short ½ life (1-2 hrs) ketorolac Toradol Oral or IM injection administration; post-op analgesia equivalent to opioids Drugs (NSAIDs) adapted from Ciccone 2007 Drugs (NSAIDs) adapted from Ciccone 2007 Generic Name Trade Name Comments meclofenamate Meclomen No apparent advantages or disadvantages compared to aspirin or other NSAIDS mefanamic acid Ponstel No advantages; often less effective and more toxic than aspirin and other NSAIDS nabumetone Relafen Effective agent with fewer side effects than most NSAIDS naproxen Anaprox, Naprosyn Similar to ibuprofen in terms of benefits and adverse effects oxaprozin Daypro Analgesic and anti-inflammatory effects similar to aspirin; may be fewer side effects Generic Name Trade Name Comments phenylbutazone Cotylbutazone Potent anti-inflammatory effects, but high incidence of side effects (10-45%) with long term use piroxicam Feldene Long ½ life (45 hrs) allows 1x/day dosing; may be better tolerated than aspirin sulindac Clinoril Relatively little effect on kidneys, but may produce more GI side effects than aspirin tolmetin Tolectin Similar to aspirin s benefits and side effects but must be given frequently (QID) due to short ½ life (1 hr) Drugs (NSAIDs) You forgot to put Celecoxib (Celebrex) on the table! COX-2 inhibitors Inhibit synthesis of inflammatory prostaglandins, while sparing synthesis of beneficial prostaglandins. Effective analgesic and anti-inflammatory with less gastric upset risk of heart attack and stroke Drugs (NSAIDs) Acetaminophen Similar to aspirin in analgesic and antipyretic effects, but lacks anti-inflammatory and anticoagulant properties. Absorbed rapidly and completely from upper GI tract, but not associated with GI irritation High doses may be toxic to the liver Inexpensive and readily available

5 NSAIDs Safety Profile Digestive upset, ulcers and liver damage Risk increases with: Age >65 Female gender smoker High BMI Diabetes, cardiovascular disease, or hypertension OTC concerns Drugs (NSAIDs) Rehabiliation Considerations OTC drugs not reported Effects of drugs complement physical therapy Side-effects (GI symptoms) usually will not interfere with therapy Opioid Analgesics 1. Moderate-severe pain Acute Chronic Opioid Analgesics Mode of Action 3 endogenous opiates: endorphins, enkephalins and dynorphins 3 opioid receptors: µ, κ, δ Opioid drugs are being developed to stimulate some receptors while blocking others Opioid Analgesics Classification of Opioid Analgesics Morphine Prototypical opioid analgesic Type Generic Name Trade Names Strong Agonist fentanyl Actiq, Duragesic, Sublimaze hydromorphone Hydrostat, Dilaudid levorphanol Lev-Dromoran meperidine Demerol Methadone Dolophine, Methadose morphine MS Contin, Roxanol, Statex, etc oxymorphone Numorphan

Classification of Opioid Analgesics Classification of Opioid Analgesics Type Generic Name Trade Names Mild-Moderate Agonist codeine hydrocodone oxycodone propoxyphene Lortab, Lorcet, Vicodin, Norco,

6 Classification of Opioid Analgesics Classification of Opioid Analgesics Type Generic Name Trade Names Mild-Moderate Agonist codeine hydrocodone oxycodone propoxyphene Lortab, Lorcet, Vicodin, Norco, Polygesic, Stagesic, etc OxyContin, Roxicodone Darvon Mixed Agonist-Antagonist butorphanol Stadol buprenorphine nalbuphine pentazocine Buprenex Nubain Talwin Type Generic Name Trade Names Antagonists nalmefene Revex naloxone Narcan naltrexone ReVia Opioid Analgesics Safety Profile Side effects: respiratory depression, sedation, psychotic effects, GI distress, increased hormonal release and inhibits neurotransmitter release Tolerance: need to progressively increase dosage to gain therapeutic effect Physical dependence: onset of withdrawal symptoms after drug is removed Opioid Analgesics Time therapy sessions to take advantage of pain relief provided by drug Hypoxia and hypercapnia may occur with exercise due to decreased respiratory rate Muscle aches and pain may be symptoms of withdrawal rather than a somatic disorder Physical agents and manual techniques can be beneficial to relieve these symptoms. Skeletal Muscle Relaxants 1. Normalize muscle excitability to decrease pain and improve motor function Spasticity Spasms 2. Often combined with NSAIDs Spasticity Result of injury to the CNS. Exaggerated stretch reflex

Spasms Skeletal Muscle Relaxants Result of musculoskeletal injuries and inflammation Continuous, tonic, involuntary contraction Mode of Action 1. Increase central inhibitory effects of GABA 2.

substance) chlorzoxazone Paraflex, Parafon Forte cyclobenzaprine Flexeril Considered the prototype of this group diazepam Valium Also anti-anxiety drug metaxalone methocarbamol Skelaxin Carbacot,

7 Spasms Skeletal Muscle Relaxants Result of musculoskeletal injuries and inflammation Continuous, tonic, involuntary contraction Mode of Action 1. Increase central inhibitory effects of GABA 2. Polysynaptic inhibitors in spinal cord Skeletal Muscle Relaxants Skeletal Muscle Relaxants Generic Name Trade Name Comments carisoprodol Soma, Vanadom Metabolized to form meprobamate (controlled substance) chlorzoxazone Paraflex, Parafon Forte cyclobenzaprine Flexeril Considered the prototype of this group diazepam Valium Also anti-anxiety drug metaxalone methocarbamol Skelaxin Carbacot, Robaxin, Skelex orphenadrine Antiflex, Norflex Norgesic is orphenadrine, aspirin, caffeine Safety Profile Side effects include: drowsiness, dizziness, headache, nausea/vomiting. Tolerance and physical dependence may occur with long-term use Skeletal Muscle Relaxants Complement physical therapy interventions Thermal, electrotherapeutic and manual techniques Effective in acute stage, but work to eliminate need for these drugs long-term Prevent re-injury with posture and body mechanics training in addition to therapeutic exercise Glucocorticoids/Corticosteroids Adrenocorticosteroids-large number released by the adrenal gland into systemic circulation Glucocorticoids: glucose metabolism, stress, inflammation and immune function Mineralocorticoids: salt retaining activity Androgenic or Estrogenic activity

Glucocorticoids Systemic Glucocorticoids Indications for use Potent anti-inflammatory, regardless of the cause Immunosuppression Generic Name betamethasone cortisone dexamethasone hydrocortisone

8 Glucocorticoids Systemic Glucocorticoids Indications for use Potent anti-inflammatory, regardless of the cause Immunosuppression Generic Name betamethasone cortisone dexamethasone hydrocortisone methylprednisolone prednisolone prednisone triamcinolone Trade Name Celestone, Diprosone, etc Cortone Decadron, Dexasone, etc Cortef, Hydrocortone Medrol Pediapred, Predalone, Orapred, Deltasone, Meticorten, Sterapred Azmacort, Aristocort Systemic Glucocorticoids Glucocorticoids Generic Name betamethasone cortisone dexamethasone hydrocortisone methylprednisolone prednisolone prednisone triamcinolone Trade Name Celestone, Diprosone, etc Cortone Decadron, Dexasone, etc Cortef, Hydrocortone Medrol Pediapred, Predalone, Orapred, Deltasone, Meticorten, Sterapred Azmacort, Aristocort Mode of Action Inhibit the expression of inflammatory proteins (cytokines) Limit the production of factors that attract leukocytes to the site of inflammation Inhibit the production of pro-inflammatory substances (protaglandins and leukotrienes) Reduce vascular permeability Glucocorticoids Glucocorticoids Safety Profile Catabolic effect on muscle, bone, ligaments, tendons and skin Altered glucose metabolism in diabetes mellitus Hypertension Peptic ulcer Retard growth in children Glaucoma Mood changes/psychosis Avoid overstressing tissues weakened by prolonged use Skin breakdown Weight bearing activities encouraged Monitor blood pressure Increased susceptibility to infection

Disease-Modifying Antirheumatic Suppress the immune response in rheumatoid arthritis Disease-Modifying Antirheumatic Type Generic Name Trade Name Comments Gold auranofin Ridaura Oral-fewer side

9 Disease-Modifying Antirheumatic Suppress the immune response in rheumatoid arthritis Disease-Modifying Antirheumatic Type Generic Name Trade Name Comments Gold auranofin Ridaura Oral-fewer side effects Gold aurothioglucose Solganal IM Gold gold sodium thiomalate Myochrysine Antimalarial chloroquine Aralen Safest type; retinal toxicity Antimalarial Plaquenil IM Similar to above azathioprine Imuran Used for severe RA, not responding to other drugs sulfasalazine Azulfidine Common use, works for 1-3 mos. Disease-Modifying Antirheumatic Disease-Modifying Antirheumatic Type Generic Name Trade Name Comments Gold auranofin Ridaura Oral-fewer side effects Gold aurothioglucose Solganal IM Gold gold sodium thiomalate Myochrysine Antimalarial chloroquine Aralen Safest type; retinal toxicity Antimalarial Plaquenil IM Similar to above azathioprine Imuran Used for severe RA, not responding to other drugs sulfasalazine Azulfidine Common use, works for 1-3 mos. Type Generic Name Trade Name Comments Gold auranofin Ridaura Oral-fewer side effects Gold aurothioglucose Solganal IM Gold gold sodium thiomalate Myochrysine Antimalarial chloroquine Aralen Safest type; retinal toxicity Antimalarial Plaquenil IM Similar to above azathioprine Imuran Used for severe RA, not responding to other drugs sulfasalazine Azulfidine Common use, works for 1-3 mos. Disease-Modifying Antirheumatic Disease-Modifying Antirheumatic Type Generic Name Trade Name Comments Tumor necrosis factor inhibitors methotrexate Rhematrex Very effective; often used first for children and adults leflunomide Arava Quick onset of effects adalimumab Humira Biologic DMARDs Subcutaneous injection TNF inhib. etanercept Enbrel Subcutaneous injection TNF inhib. infliximab Remicade IV every 8 wks. Type Generic Name Trade Name Comments hydroxychloroquine Immunosuppressant Immunosuppressant hydroxychloroquine Immunosuppressant Immunosuppressant hydroxychloroquine Immunosuppressant Immunosuppressant Antimetabolite Antimetabolite Antimetabolite Antimetabolite Tumor necrosis factor inhibitors methotrexate Rhematrex Very effective; often used first for children and adults lefunomide Arava Quick onset of effects adalimumab Humira Biologic DMARDs Subcutaneous injection TNF inhib. etanercept Enbrel Subcutaneous injection TNF inhib. infliximab Remicade IV every 8 wks.

10 Disease-Modifying Antirheumatic Dietary Considerations Fish oil Fruits and vegetables Meat and protein Disease-Modifying Antirheumatic Monitor symptoms and changes in drug regimen Headache and nausea, joint pain and fatigue Monitor for signs of infection Inspect skin for bruising and rash Disease-Modifying Osteoarthritic Drugs (DMOADs) Improve the viscosity and function of synovial fluid (viscosupplementation) Hyaluronan (Hyalgan, Synvisc) injected into joint to restore normal viscosity and lubricating properties of synovial fluid Series of 2-10 weekly injections Results last 6-12 months. Disease-Modifying Osteoarthritic Drugs (DMOADs) Protect articular cartilage Dietary supplements: Glucosamine (1500 mg/day), Chondroitin Sulfate (1200 mg/day) Provide key ingredients for production of gycosaminoglycans, proteoglycans and hyaluronic acid May take weeks to months to note benefits. Disease-Modifying Osteoarthritic Drugs (DMOADs) Local pain and swelling after injection Possible GI upset with oral supplements Complementary to rehab goals of increased activity and quality of life. Local Anesthetics Block peripheral or spinal cord nerve transmission Delivery Techniques: Topical: minor burns, abrasions, inflammation Transdermal: patch or ionto/phonophoresis Infiltration: for suturing

Local Anesthetics Delivery Techniques Peripheral nerve block Minor: affects one distinct nerve Major: several peripheral nerves or plexus May use catheter implanted after surgery Central neural

Anesthetics Delivery Techniques: Sympathetic block Inject area of sympathetic ganglion supplying area for treatment of CRPS IV regional anesthesia (Bier Block) Inject peripheral vein for treatment of

11 Local Anesthetics Delivery Techniques Peripheral nerve block Minor: affects one distinct nerve Major: several peripheral nerves or plexus May use catheter implanted after surgery Central neural blockade Epidural: injection into epidural space Spinal: injection into subarachnoid space May be used as an alternate to general anesthesia for surgery Indwelling catheters for chronic pain Local Anesthetics Delivery Techniques: Sympathetic block Inject area of sympathetic ganglion supplying area for treatment of CRPS IV regional anesthesia (Bier Block) Inject peripheral vein for treatment of CRPS or local surgery Local Anesthetics Names use the -caine suffix procaine/novocaine lidocaine/xylocaine bupivacaine/marcaine Type chosen by administration, onset and duration of action. Local Anesthetics Mode of Action Closes (inactivates) sodium channels in nerve membrane and prevents depolarization Effective when only a short portion of the axon is affected Local Anesthetics Safety Profile Systemic effects: Initial CNS excitation: sleepiness, confusion, agitation, possible seizures CNS depression: respiratory depression, decreased heart rate and force of contraction. Early symptoms: tinnitus, agitation, restlessness; changes in ECG, fatigue, dizziness Local Anesthetics Consider transdermal phono/iontophoresis Schedule rehab sessions after injections to take advantage of anesthetic properties Sensation and motor function may be decreased below the level of epidural or spinal block

Pharmacovigilance Pharmacology Resources https://online.epocrates.com http://www.nlm.nih.gov/medlineplus/drugi nformation.html http://www.pdrhealth.com/drugs/drugsindex.aspx# http://www.drugs.com Pharmacology Resources http://www.

org/ References for Pharmacology Self- Study Module Brookfield WP. Pharmacologic Considerations for the Physical Therapist. In:Boissonnault WG, ed. Primary Care for the Physical Therapist.

12 Pharmacovigilance Pharmacology Resources nformation.html Pharmacology Resources cle.htm Medscape from WebMD References for Pharmacology Self- Study Module Brookfield WP. Pharmacologic Considerations for the Physical Therapist. In:Boissonnault WG, ed. Primary Care for the Physical Therapist. Examination and Triage. St. Louis, MO: Saunders Elsevier; 2005: Ciccone CD. Pharmacology in Rehabilitation. Philadelphia, PA. F.A. Davis Company; Gladson B. Pharmacology for Physical Therapists. St. Louis, MO: Saunders Elsevier; Harris Interactive, Inc. Attitudes and Beliefs About the Use of Over-the-Counter Medications: A Dose of Reality. January Available at: Katzung BG, ed Basic & Clinical Pharmacology. New York, NY. The McGraw-Hill Companies, Inc; Koester MC, Dunn WR, Kuhn JE, Spindler KP. The efficacy of subacromial corticosteroid injection in the treatment of rotator cuff disease: A systematic review. J Am Acad Orthop Surg. 2007;15(1):3-11.

MUSCULOSKELETAL PHARMACOLOGY. A story of the inflamed

MUSCULOSKELETAL PHARMACOLOGY. A story of the inflamed MUSCULOSKELETAL PHARMACOLOGY A story of the inflamed 1 INFLAMMATION Pathophysiology Inflammation Reaction to tissue injury Caused by release of chemical mediators Leads to a vascular response Fluid and