Drugs for Pain

Question 1

aspirin

Answer 1

• NSAID IRREVERSIBLY inhibits COX-1 and 2
• leads to decreased PG and TxA2
• long lasting inhibition of platelets
• used for pain, fever, inflammation, for thinning blood
• risk of ulcers (loss of PG in GI), bleeding, Rey syndrome in children with viral illness

Question 2

ibuprofen

Answer 2

• NSAID reversibly inhibits COX-1 and 2
• leads to decreased PG synth
• used for pain, fever, inflammation
• risk of fetal renal dysfunction and oligohydramnios, MI, stroke, GI bleed

Question 3

naproxen

Answer 3

• NSAID reversibly inhibits COX-1 and 2
• leads to decreased PG synth
• used for pain, fever, inflammation
• longer half life

Question 4

celecoxib

Answer 4

• NSAID SELECTIVE COX-2 inhibitor
• decreased formation of PG
• used for pain, fever, and inflammation
• risk of fetal renal dysfunction and oligohydramnios, SERIOUS risk of MI and stroke, GI bleed

Question 5

acetaminophen

Answer 5

• MOA unknown
• used for fever, pain, inflammation
• toxic when glutathione is depleted and can cause liver failure and death

Question 6

morphine

Answer 6

• opioid active in CNS
• inhibits ascending pain pathways
• risk of resp depression, constipation, CNS depression

Question 7

amitriptyline

Answer 7

• tricyclic antidepressant
• inhibition of NE and 5-HT reuptake by the presynaptic neuronal membrane pump
• used for major depressive disorder, chronic fatigue, fibromyalgia, neuropathic pain
• increased risk of suicidal behavior, anticholinergic effects, bleeding, sinus tach, serotonin syndrome

Question 8

duloxetine

Answer 8

• SNRI, inhibitor of 5-HT and NE reuptake (slightly DA also)
• treatment for anxiety, fibromyalgia, depression, neuropathic pain
• increased risk of suicide, mania, bleeding, sexual dysfunction

Question 9

pregabalin

Answer 9

• Binds to CNS alpha-2-delta subunit of calcium channels
• inhibits excitatory neurotransmitter release
• used for fibromyalgia, neuropathic pain, peripheral neuropathy, and seizures
• risk of skin hypersensitivity, somnolence, thrombocytopenia…

Question 10

tramadol

Answer 10

• partial agonist at μ-opioid receptors in the CNS
• inhibits reuptake of NE and 5-HT
• inhibits ascending pain pathways
• used for severe pain
• risk of resp or CNS depression, addiction and abuse

Question 11

ketamine

Answer 11

• noncompetitive NMDA receptor antagonist
• cataleptic like state with dissociation from environment
• used for pain and induction of general anesthesia

Question 12

dexmedotomidine

Answer 12

• selective alpha 2 receptor agonist in the brainstem
• used for general anesthesia maintenance and pain
• risk of hypotension, bradycardia, and sinus arrest

Question 13

ziconotide

Answer 13

• binds to N-type voltage sensitive Ca channels located on nociceptive afferent nerve of the dorsal horn
• blocks excitatory NT transmission and reduces pain sensation
• risk of severe psychiatric symptoms

Question 14

sumatriptan

Answer 14

• selective 5-HT1B and 5-HT1D agonist
• causes vasoconstriction in intracranial blood vessels to reduce migraine pain
• risk of prolonged QT interval, MI, HTN, stroke

Question 15

lasmiditan

Answer 15

• selective 5-HT1F agonist
• decreased stim of the trigeminal system for migraine pain
• risk of dizziness, CNS depression, serotonin syndrome

Question 16

ubrogepant

Answer 16

• calcitonin gene related peptide receptor antagonist

- inhibits pathologic dilation of intracranial arteries for migraine

Question 17

dihydroergotamine

Answer 17

• ergot alkaloid
• binds many receptors
• constricts blood vessels, and is used for migraine
• inhibitor of CYP3A4
• associated with cardiac fibrosis