Analgesic Drugs

Question 0

Morphine (MS Contin)

Answer 0

Opioid Analgesic
Used for pain relief.
MOA - potent mu3 R agonist. Raises pn threshold at brain stem and spine and alters perception of pn. Often used in acute MI cases to decrease pn and anxiety. Can be PO, PR, IM or IV.
SFx: Respiratory depression, dependency, miosis (pinpoint pupils), itching dt histamine release. N/V, consitpation, and can cross placenta.

Question 1

Opioid Analgesics

Answer 1

Directly interfere with pain transmission as well as pt’s perception and response to pain. Opioid receptor sites are distributed throughout the brain, spinal cord, GI tract, and perip. nervous system. Analgesic properties of opioids are mediated by the mu class of receptors.

Question 2

Fentanyl (Duragesic)

Answer 2

Opioid analgesic used for pain relief and anesthesia.
MOA - similar to morphine but 80-fold more potent. Can be in patch or PO “lollypop” form.
SFx: Dependence, N/V, respiratory depression, constipation. Pts on CYP450 inhibitors may have lethal blood levels of fentanyl.

Question 3

Codeine

Answer 3

Opioid analgesic used for pn relief and as an anti-tussive.
MOA - opioid R agonist. Much weaker than morphine. May be PO, IV, IM, SQ. Much lower risk of dependence.
SFx: sedation, constipation.

Question 4

T3

Answer 4

Acetaminophen (300mg) + Codeine (30mg)

Question 5

T4

Answer 5

Acetaminophen (300mg) + Codeine (60mg)

Question 6

Tramadol (Ultram)

Answer 6

Centrally acting opioid analgesic.
MOA - mild agonist of mu receptors and also affects reuptake of 5HTP and NE
SFx: respiratory depression is not significant at normal therapeutic doses.

Question 7

Methadone

Answer 7

Synthetic, orally-active opioid with longer duration of action than morphine, and also less euphoria. Used primarily as a controlled withdrawal substance for heroin and morphine addicts. Dependence can develop but it is much less severe than heroin or morphine.

Question 8

Naloxone (Narcan)

Answer 8

Opioid antagonist. Used in cases of opioid OD to reverse coma and respiratory depression. Binds with very high affinity to opioid receptors but DOES NOT stimulate the R. May be PO or IV. Onset within 30’. Notably, does not have any affect on individuals not using opioids.

Question 9

Aspirin (Acetylsalicylic acid)

Answer 9

NSAID, used for inflammation, pn and fever.
MOA - Irreversible inhibition of COX-1 and COX-2 enzymes. This decreases PG production throughout the body. Can be PO or PR.
SFx: GI irritation, peptic ulcer, increased bleeding, Reye’s syndrome, salicylism. There is no antidote to ASA OD.

Question 10

Ibuprophen (Motrin, Advil)

Answer 10

NSAID. Used for pn, inflammation, fever.
MOA - Reversible inhibition of COX-1 and COX-2 enzymes. PO or PR.
SFx: No increased risk of Reye’s syndrome. May damage stomach lining. Can increase BP due to action of kidney bloodflow at glomeruli.

Question 11

Celecoxib (Celebrex)

Answer 11

NSAID. Used for inflammation, pn, and tx of adenomatous polyps.
MOA - Reversible, selective COX-2 inhibition. PO.
SFx: Does not inhibit platelet aggregation or cause GI bleed. Unclear but extant evidence of cardiovascular disease risk increase.

Question 12

Acetaminphen (Tylenol)

Answer 12

NSAID for pn and fever.
MOA - not well understood. Weak peripheral blockade of PG synthesis with stronger effect centrally at hypothalamus. PO, PR. No additional risk of GI bleeding, no development of Reye’s syndrome.
SFx: Hepatotoxic metabolic byproduct (NAPQI) created by acetaminophen metabolism. Dose over 7g in 24 hour can cause liver damage. NEVER use with alcohol or in pts with liver dz. Antidote of OD is NAC