210 pharm
Topical Anesthetics
Definition: Topical anesthetics are medications applied to the skin or mucous membranes to numb the area and decrease pain sensation.
Examples: Lidocaine is a common topical anesthetic.
Key Use: Provides no pain or decreases sensitivity to pain.
Inflammation
Key Characteristics of Inflammation:
- Redness (alternatively referred to as Dreadness)
- Swelling
- Pain
- WarmthPage Reference: For more details, see Table 24.1 on page 279.
Inflammation Phases:
- Vascular Phase: Occurs within 10 to 15 minutes after injury, characterized by vasodilation and leukocyte infiltration.
- Delayed Phase: Following the vascular phase.
Chemical Mediators and Enzymes
Prostaglandins:
- Chemical mediators involved in inflammation, isolated from exudate (drainage from an inflammatory site).Cyclooxygenase (COX) Enzymes:
- COX-1: Protects the stomach lining and regulates blood platelets.
- COX-2: Triggers inflammation and pain.Aspirin and Its Mechanisms:
- Inhibits prostaglandin biosynthesis.
- Affects hypothalamic temperature regulation and helps with platelet aggregation.
Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)
NSAIDs Classifications:
- Nonselective NSAIDs: Inhibit both COX-1 and COX-2 (e.g., Aspirin, Ibuprofen).
- Selective NSAIDs: Primarily inhibit COX-2 (e.g., Celecoxib).Common NSAID Use Cases:
- Pain relief in inflammatory conditions (e.g., osteoarthritis, rheumatoid arthritis).
- Antipyretic effect: used to reduce fever.
- Analgesic properties: relieve pain.Aspirin:
- Oldest anti-inflammatory used for analgesia and antipyresis.
- Commonly used nowadays for blood thinning rather than pain relief.
Side Effects and Precautions
Common Side Effects of Aspirin:
- Dizziness, headache, nausea, abdominal pain, loss of appetite (anorexia), confusion, sweating (diaphoresis), agitation, lethargy, gastritis, vomiting, itching (pruritus), rash, dehydration.Adverse Reactions:
- Potentially life-threatening issues, e.g., hemolytic anemia, thrombocytopenia, renal or hepatic failure, pulmonary edema, Stevens-Johnson syndrome, GI bleeding, ulcers, and perforation.Cautions:
- Avoid use in children with flu-like symptoms due to the risk of Reye syndrome (brain and liver swelling).
Ibuprofen
Common Uses: Pain relief for headaches, menstrual pain, osteoarthritis, and rheumatoid arthritis.
Action Mechanism: Blocks COX-1 and COX-2, reducing inflammation and relieving pain.
Side Effects & Adverse Reactions: Similar to those of aspirin, including renal toxicity and risk for GI bleeding.
Gout and Medications
Gout Definition: An inflammatory condition characterized by deposits of uric acid crystals in joints, commonly affecting the big toe.
Causes: Urinary excretion deficits or overproduction of uric acid.
Medications for Gout:
- Allopurinol: Inhibits xanthine oxidase to decrease uric acid production.
- Dietary Recommendations: Increase fluid intake, avoid alcohol, organ meats, and high-purine foods.Side Effects and Adverse Reactions: Gastrointestinal upset, renal impairment, and liver reactions.
Acetaminophen (Tylenol)
Use Cases: Reduces pain and fever but lacks anti-inflammatory properties of NSAIDs.
Dosage Information: Maximum recommended dose is 4000 mg per day, though limiting to 2000 mg is advised for frequent users to avoid hepatotoxicity.
Potential Side Effects: Nausea, constipation, and headache.
Life-Threatening Effects: Hepatic failure and renal toxicity.
Opioid Analgesics
Definition: Strong pain relievers derived from opium; used for moderate to severe pain.
Common Drugs: Morphine, codeine.
Mechanism of Action: Binds to opiate receptors in the CNS to modify pain perception.
Side Effects: Drowsiness, constipation, respiratory depression, hypotension, and potential for dependence.
Monitoring: Respiratory rate, consciousness level, and pain levels.
Antidotes: Naloxone (Narcan) is used to reverse opioid overdoses.
Patient Controlled Analgesia (PCA)
Definition: Allows patients to self-administer prescribed doses of pain medication via an IV or pump system.
Mechanism: A lockout mechanism prevents overdosing by limiting the frequency of administration.
Nursing Interventions & Patient Education
For NSAIDs:
- Monitor for signs of GI distress, educate about potential interactions with other drugs (e.g., anticoagulants).
- Ensure patients take medications with water or during meals to reduce gastric issues.For Opioids:
- Observe for respiratory function; assess for sedation, pain relief, vital signs.
- Educate the patient on the importance of monitoring their substance use and use alternative pain control methods where possible.