Drugs for Pain and Inflammation Flashcards
Name the two categories of drugs that treat pain
- Opioid
2. Nonopioid
What severity of pain do opioids relieve
Moderate to severe
What is the prototypical opioid analgesic used for comparing other drugs to?
Morphine
What are the 3 opioid receptors that effect spinal and supra spinal analgesia?
Mu, Kappa, and Delta
Opioid receptor that causes sedation, respiratory depression, constipation, inhibits neurotransmitter (ACh, dopamine) release, increases hormonal release (prolactin, growth hormone)
Mu
Opiod receptor that causes sedation, constipation and psychotic effects
Kappa
Opioid receptor that increases hormonal release (growth hormone) and inhibits neurotransmitter (dopamine) release
Delta
The most important opioid receptor in mediating the analgesic effects of morphine and other opioids; located in specific locations in the brain and spinal cord; opioids have high affinity to this receptor type; mediate problematic side effects
Mu
Opioids that selectively stimulate _____ and _____ receptors may provide sufficient analgesia while less likely causing respiratory depression and abuse if they avoid or block _____ receptors (mixed agonist-antagonist opioids)
Kappa and Delta; Mu
What is classification of different opioids based on?
Their interaction with opioid receptors
Opioid classification: Used to treat severe pain; high affinity for certain receptors (primarily mu); i.e., morphine, fentanyl, hydromorphone
Strong agonists
Opioid classification: not as high of an affinity or efficacy as strong agonists; i.e., codeine, hydrocodone, oxycodone
Mild-to-Moderate agonists
Opioid classification: Exhibit some agonist and antagonists like activity at the same time; produces adequate analgesia while decreasing the risk of respiratory depression; i.e., butorphanol, nalbuphine, pentazocine
Mixed agonist-antagonist
Causes analgesia by binding to activating kappa receptors while blocking (or partially activating) mu receptors
Butrophanol
What is used to treat opioid overdoses and addiction? u
Antagonists
Rapidly and dramatically reverse the respiratory depression which usually causes death in a person
Nalmefene and naloxone
Used in conduction with with behavioral therapy to maintain an opioid-free state in people recovering from addiction; blocks receptors so that if a person shoots up with heroin, they will not feel the effects
Naltrexone
What metabolically inactivates opioids?
Liver
How are opioids excreted?
Kidneys excrete the drug metabolite
How do opioids work?
Inhibit afferent pain transmission, allow descending pathways to become more helpful in controlling pain by reducing painful sensations at the spinal cord level
When compared to other forms of analgesia, why are opioids unique?
The alter the perception of pain rather than eliminating the painful sensation entirely
Other than pain management, what are opioids used for?
- Anesthesia (premedication or adjunct)
- Cough suppression (codeine)
- Decrease GI motility (in cases of diarrhea
- Adjunct for acute pulmonary edema
How long does it take to decrease tolerance to the point where you can begin taking the original prescribed dose?
2 weeks
When will doses of opioids need to be increased?
After 2-3 weeks
Problems with addiction, tolerance, and dependence are minimized when opioid medications are used _______.
Therapeutically
Strong opioid agonist used to treat addiction; used as substitute for the abused opioid and slowly tapered down and withdrawn along with the pt in counseling; low success rate
Methadone
Mixed agonist-antagonist (agonist at mu, antagonist at kappa); sustains opioids effects to prevent withdrawal; blocks cellular changes that promote addiction
Buprenorphine
How would opioid analgesics in patients requiring rehab be helpful?
Pt is in less pain, so more able to do exercises
How would opioid analgesics in patients requiring rehab be detrimental?
Pt could injure themselves being confused, could be drowsy, could affect respiratory function
When should a pt take their opioid relative to their rehab?
30 mins - 1 hour
What is something else you may have to watch out for while at work?
Coworkers or family members stealing opioids
What are the uses for Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)?
- Decrease inflammation
- Relieve mild-to-moderate pain
- Decrease elevated body temp
- Decrease blood clotting
What does NSAIDs inhibit the synthesis of?
Prostaglandins
Produced by all cells except RBCs; hormones that act locally to help regulate cell fxn under normal conditions; thromboxjnes and leukotrienes also derived from the same precursor
Prostaglandins
Name 3 Eicosanoids
- Prostaglandins
- Trombones
- Leukotrienes
What enzymes do NSAIDs inhibit?
COX
The blockage 2 COX enzymes causes both beneficial and adverse side effects. Which enzyme is it beneficial to block and which causes side effects if blocked?
COX2 is beneficial; this produces pain and inflammation, and overactive enzymes cause problems
COX1 causes side effects; enzyme produces prostaglandins that protect the stomach lining, maintain renal function, and regulate normal platelet activity
What is the primary concern for COX2 selective drugs?
Increased risk for serious CV events such as heart attack and stroke
What is the only COX2 inhibitor on the market?
Celecoxib (Celebrex)
Equal to NSAIDs in terms of analgesic and antipyretic effects; no anti-inflammatory or anticoagulant effects; not associated with GI irritation; High doses are toxic to the liver and can be fatal
Acetaminophin
