Chapter 11 Analgesics Flashcards
What are analgesics?
Medications that relieve pain without causing lack of consciousness. Include opioids, non-opioids (which include NSAIDs).
Opioids
- Pain relievers that contain opium or or synthetically derived opium. Used mainly to relieve moderate to severe pain. Opioids are also used for cough, diarrhea, and anesthesia.
- Adverse effects include hypotension, palpitations, flushing, sedation, disorientation, euphoria, lightheadedness, seizures, nausea, vomiting, constipation, urinary retention, itching, rash, and respiratory depression.
- Physical and psychological dependence is common.
- Opiate is a natural drug and opioid is synthetic (both bind to opiate receptors in the brain).
Nonopioids analgesics
- Has analgesic and antipyretic effects. Has little to no anti-inflammatory effects. Is available OTC.
- Used for mild to moderate pain, fever, and for those that cannot take Aspirin.
- Most common example is acetaminophen
- Dangerous interactions may occur with if taken with alcohol
- Constipation is a common side effect. Also monitor for respiratory depression.
Acute pain
Pain that is sudden in onset, usually subsides when tretated, and typically occurs over less than a 6 week period
Addiction
Strong psychological and physical dependence on a drug or other psychoactive substance, usually resulting from habitual use, that is beyond normal voluntary control
Agonist
A substance that binds to a receptor and causes a response
Agonist-antagonist
A substance that binds to a receptor and causes a partial response that is not as strong as that caused by an agonist
Analgesic ceiling effect
A phenomenon that occurs when a given pain drug no longer effectively controls a patients pain despite the administration of the highest safe dosages
Antagonist
An agent that binds to a receptor and prevents (blocks) a response, resulting in inhibitory or antagonistic effects
Breakthrough pain
Pain that lingers despite doses of a long acting dosage form for every 12 hours
Gate theory
A common and well-described theory of pain transmission and pain relief. It uses a gate model to explain how impulses from damaged tissues are sensed in the brain.
Neuropathic pain
Pain that results from a disturbance of function or pathological change in a nerve
Nociceptive pain
Pain that arises from mechanical, chemical, or thermal irritation of peripheral sensory nerves (example after surgery)
NSAIDs
Analgesics that possess anti-inflammatory and antipyretic activity but they are not steroids
Partial angonist
A drug that binds to a receptor and causes an activation response and that is less than that caused by a full agonist
Psychogenic pain
Pain that is of psychological origin in nature but is actual pain in the sense that pain impulses travel through nerve cells
Referred pain
Pain occurring in an area away from the organ of origin
Somatic pain
Pain that originates from skeletal muscles, ligaments, or joints
Persistent pain
Persistent or reoccurring pain that is often difficult to treat. Typically it is pain that lasts longer than 3 months
-Neurological pathways are completely different for persistent and acute pain
Pain
Pain is complicated because it it what the patient says it is. It is subjective
Visceral Pain
Pain that originates from organs or smooth muscles
Superficial Pain
Pain that originates from the skin or mucous membranes
Vascular Pain
Pain that results from pathology of the vascular or perivascular tissues
Phantom Pain
Pain experienced in a body part that has been surgically or traumatically removed
Pain transmission
- A fibers cause acute, severe pain and C fibers do not cause as acute of pain as A.
- Tissue injury produces substances and these substances stimulate the nerve endings
- The fibers travel up the spinal cord and to the brain
Pain Tolerance
- The amount of pain a patient can endure without its interfering with normal function
- It varys from person to person
Pain Threshold
- The level of stimulus needed to produce the perception of pain
