Pain

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Analgesics (Non-NSAID)

acetaminophen=Tylenol: AVL: PO (tab325,500, 650(ER), liquid). IND: Pain (ex.arthritis, HA, strain/sprains), fever. ADM: Take w/ or without food. AE: Dizziness6%, drowsiness9%, headache5%, diar2%, stomach upset1%, naus3%. AUX: Don’t crush (ER tabs). MON: Kidney and liver fxn if long term Tx. DOS: Pain: Max=4g/d divided TID/QID.
OTH: Doesn’t reduce inflammation. Aka paracetamol.

 

Ergotamines

IND: Migraines. EVD: More naus but less chest pain vs triptans. CI: Don’t use within 12h of triptan or 24h of naratriptan.
dihydroergotamine (DHE)=Migranal: AVL: IM, IV, SubQ, nasal spray. IND: 1st line for severe/ultra severe attacks. DOS: IV, IM SubQ: 0.5-1mg. May repeat after 1h. Max=4 doses/d. OTH: Give metoclopramide 10mg IV or prochlorperazine 5mg IV before administering DHE.


 

Janus Kinase (JAK) Inhibitors

baricitinib=Olumiant: AVL: PO (tab2mg). IND: Reducing signs and symptoms of mod-severe rheumatoid arthritis in adults who have inadequate response to >1 DMARD. MOA: Selective and reversible inhibitor of Janus kinases (JAKs), which are enzymes involved in hematopoiesis, inflammation and immune function. This inhibition results in a reduced pro-inflammatory response, as well as modulation of lymphocyte activation/proliferation and cytokine production. ADM: T w/ or without food. AE: Increase in creatine phosphokinase, hypercholesterolemia, pharyngitis, naus, UTI, URTI, HTN, headache, nasopharyngitis, bronchitis, higher risk for developing serious infections (ex active tuberculosis), GI perforation, lymphoma, shingles, liver enzyme elevation, DVT/PE. CI: Shouldn't be started if lymphocyte count <0.5 x 109 cells/L, neutrophil count <1 x 109 cells/L or hemoglobin <80 g/L. Test for TB before starting. DI: Live vaccines not recommended (update immunizations before starting). Not recommended w/ other JAK inhibitors (tofacitinib), DMARDs or potent immunosuppressants. MON: Test for TB periodically. DOS: STD=2mg once/d. No dose adj in mild renal impairment. Not recommended in mod-severe renal impairment (eGFR<60mL/min/1.73 m2). No dose adj in mild-mod hepatic impairment. Not recommended in severe hepatic impairment. OTH: To be used w/ methotrexate, but can be monotherapy if methotrexate not tolerated. Second oral JAK kinase inhibitor in Canada.
tofacitinib=Xeljanz OTH: First oral JAK inhibitor in Canada.


 

Muscle Relaxers

cyclobenzaprine=Flexeril: AVL: PO. IND: Fibromyalgia, muscle spasms/pain. AE: Fatigue35%, dizziness10%, dry mouth25%, urinary retention, increased IOP. May impair driving. CI: Safety <15yo not established. DI: MAOI, serotonergic drugs (serotonin syndrome). PK: t1/2= 18h. F=33-55%. High PB. Met by 1A2 (main), 3A4, and 2D6. DOS: 5mg TID as effective as 10mg TID w/ less sedation. Shouldn’t be used >3 weeks. OTH: Has similar structure and AE as tricyclic antidepressants.

 

Opioids

OTH: Naloxone used in overdose.
buprenorphine+naloxone=Suboxone: AVL: SL tabsbuprenorphine/naloxone 8/2 and 2/0.5mg. IND: Opioid dependence Tx. MOA: Buprenorphine is a high affinity partial opioid agonist (at mu and kappa). It can bump other opioids off of the mu receptors leading to abbrupt withdrawl. Naloxone is a high affinity mu antagonist. It has poor oral F but is added to prevent IV use. Because t1/2 is shorter for naloxone than buprenorphine, you can still get high if injected. EVD: Has lower overdose, mortality, toxicity risk vs methadone. Has less sedation vs methadone. Doesn't prolong QTc like methadone. May be less effective vs methadone (especially those w/ heavy dependence). Easier to D/C vs methadone. ADM: Drinking water before dose helps tabs dissolve faster. AE: Headache, insomnia, anxiety, naus, abdominal pain, const, sweating, LFT elevationrare. CI: Opioid intoxication. PRG: Crosses placenta. Associated w/ neonatal abstinence syndrome (NAS) but may be less severe vs methadone. Growing evidence says that buprenorphine has better outcomes for mom and baby however lack of evidence means Suboxone is not approved for use in prg and methadone remains preffered choice. LAC: Compatible. Lacking evidence for naloxone component but not orally bioavaible so should not have effect. DI: 3A4 inducers and inhibitors (less susceptible vs methadone due to ceiling effect). Sedatives/hypnotics could lead to respiratory depression. Anticholinergics can make const worse. PK: Sublingual F=28-51%. Oral F~0%. Onset=30-60min. Peak effect=1-4hrs. Vd=4-5L/kg. t1/2=28-37hrs. Duration=48-72hrs. Time to steady state=5-10d. PB=96%. Met by 3A4 and 2C8. Excreted mainly in feces but also urine. MON: Clinical Opiate Withdrawl Scale (COWS) used to measure withdrawl and adjust dose. DOS: Pt specific depending on degree of tolerance, severity of withdrawl and risk factors (ex. use of benzos). Can be titrated faster than methadone due to increased safety. Start=2-6mg. Second dose on day 1 can be given after prescriber assessment (>3hrs after first dose). If signs of intoxication decrease dose by 2mg. If withdrawal present, increse dose by 2-4mg on day 2 or 3. Should reach optimal dose in 1-2wks. Max=24mg/d. Pts allowed to miss 4 doses but must get new Rx if 5 doses are missed. OTH: If switching from methadone to Suboxone, methadone dose should be decreased to <30mg and should be completely off methadone for 3d to avoid precipitated withdrawal.


buprenorphine implant=Probuphine: AVL: 80mg subdermal implant. IND: Opioid dependence in adults stabilized on <8mg of sublingual buprenorphine. MON: Combine w/ counselling and psychosocial support. DOS: Each dose has 4 implants inserted subdermally in the inner side of the upper arm by a trained professional. Left in for 6 months of Tx and then removed. Can replaced w/ new implants in opposite arm at the time of removal if continued Tx desired. OTH: Drug class=partial opioid agonist. Each implant is a sterile flexible ethylene vinyl acetate rod (length=26mm), diameter=2.5mm).
codeine: AVL: Oral, IM, SubQ.
methadone=Methadose=Metadol-D: AVL: PO (tab, soln1mg/mL and 10mg/mL, powder). IND: Tablets are only indicated for pain management. MOA: EVD: Pts 3X less likely to be "using" while on methadone than without. Mortality rate is 1/3 when taking methadone vs no Tx. Pt retention in rehab programs is increased. Reduced risk of HIV and Hep C. Criminal activity decreases. Methadone is better at retaining pts vs Suboxone. ADM: Morning is preferrable so pt won't sleep during overdose. Space doses by >15hrs. Methadone typically diluted w/ tang (qs to 100mL). Can also use crystal light. AE: Prolonged QT (especially >120mg), constipation. Increased mortality risk early in Tx CI: Severe respiratory problems. PRG: Crosses placenta. Improved pregnancy outcomes vs no Tx. Not terratogenic but associated w/ neonatal abstinence syndrome (NAS). May need increased dose due to increased clearance and Vd. Methadone in apple juice instead of OJ may help w/ naus/vom. LAC: Risk of serious harm (including death) to children exposed through breasmilk. DI: 3A4 inducers or inhibitors. Sedatives/hypnotics could lead to respiratory depression. Anticholinergics can worsen const. PK: t1/2=22-48hrs. Duration=24-36hrs. Onset=30min. F=80%. Peak plasma concentration=2-4hrs. Vd=4-5L/kg. Time to steady state=5-7d. PB=85-90%. Similar potency to morphine. Metabolized by 3A4major, 1A2minor, 2B6minor, 2C8minor, 2C9minor, 2C19minor, 2D6minor. Excreted in urine and feces. COS: NS college requires use of 10mg/mL soln. AUX: Methadone specific label, store in locked box, refrigerate/shake well. MON: ECG before starting is recomended if at risk for Torsades and periodically when dose >150mg. DOS: Start: 30mg/d or less. If abstinent for >7d, starting dose should be <10mg/d. Max dose increase=10mg q3d. If also taking benzos max recommended dose=120mg/d. If dose >150mg/d monitor ECG for QT prolongation. Length of Tx is pt specific. Always once/d unless using for pain. Pts allowed to miss 2 doses but must get new Rx if missed 3. OTH: Methadone decreases likelihood of euphoria if taking other opioids at the same time. Death has happened w/ dose as low as 40mg. If dose is vomited within 15min and vomit is witnessed then a replacement dose (50% of full dose) can be given. Need new Rx.


morphine: IND: During MI.

 

Selective Serotonin Receptor Agonists

IND: Migraines. MOA: Agonist at 5HT1B/1D. EVD: All triptans equally effective but can have different individual response. Alleviates headache pain, naus, vom, photo/phonophobia. Can combine w/ NSAID for better efficacy. AE: Chest discomfort, fatigue, dizziness, drowsiness, naus, throat symptoms. DI: Don’t use within 24hrs of another triptan or DHE. OTH: Aka Triptans
almotriptan=Axert: AVL: PO. DOS: 6.25-12.5mg at start of headache. Can repeat in 2h. Max=2 doses/d.


eletriptan=Relpax: AVL: PO. DOS: 20-40mg at start of HA. Can T 20mg after 2h. Max=40mg/d. doses/d.


frovatriptan=Frova: AVL: PO. DOS: 20-40mg at start of headache. Can T 20mg after 2h. Max=40mg/d.


naratriptan=Amerge: AVL: PO (D shaped tab). DOS: Adj for renal fxn. 1-2.5mg at start of headache. Can repeat after 4h. Max=5mg/d.


rizatriptan=Maxalt: AVL: PO (tab, oral disintegrating tab). DOS: 5-10mg at start of HA. Can repeat in 2h. Max=20mg/d.


sumatriptan=Imitrex: AVL: PO (tab25, 50, 100mg, dissintegrating film (DF)), intranasal5, 20mg. SubQ6mg. IND: Tx of migraine w/ or without aura. AE: 100mg tabs caused: naus11%,dizziness6%, neck/jaw/throat pressure or pain5%, vom4%, headache3%, throat/tonsil symptoms2.3%, abdominal pain2%. CI: Heart conditions (ex. tachycardia) (can increase BP), liver impairment. MAOI CI if taken within last 2 weeks. DOS: PO: 25-100mg at start of headache. Can repeat in 2h. Max=200mg/24h. SubQ: 6mg. Can repeat in 1h. Max=2 injections(12mg)/24h. Intranasal: 5-20mg. Can repeat in 2h. Max=40mg/24h.


zolmitriptan=Zomig: AVL: PO (tab, oral disintegrating tab), intranasal. DOS: PO: 2.5-5mg at start of headache. Can repeat in 2h. Max=10mg/d.


 

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