Analgesics Flashcards
Anti-migraine medications (4)
- Perfenazine
- Rizatriptan
- Natalizumab
- Zolmitripan
Triptan (riza or zolmi) mechanism of action
Selective serotonin agonists —> 5-HT1b/1d
- Vasoconstriction
- Inhibit trigeminal nerve nociception
- Inhibit vasoactive peptide secretion
Triptan side effects
- Paresthesia, cold sensation
- Serotonin sx
- Hypertension
- Vasospasm = ischemia
When should triptans NOT be given?
Within 24 hrs of ergot derivate, another 5HT agonist or SSRIs —> coronary spasm of serotonin sx
History of coronary artery disease or hypertension
Triptan ADME
A: oral, SC, nasal
D: low bound to proteins, cross placenta
M: riza = MAO; zolmi = CYP1A2 and MAO
E: urine
Perphenazine mechanism of action
D2 antagonist
—> antipsychotic 1st gen
—> extrapyramidal effects, strong antiemetic
Perphenazine main uses (3)
- Schizophrenia
- Acute anxiety
- Severe nausea and vomiting
Perphenazine side effects (6)
- Extrapyramidal
- Neuroleptic malignant sx = more reflex, rigidity
- Hyperprolactinemia
- Hypotensino
- Weight gain
- CNS depression, seizures
Perphenazine ADME
A: oral
D: protein bound, widely distributes, crosses placenta
M: CYP2D6
E: urine and feces
Natalizumab mechanism of action
Target: a4 integrin
—> affects WBC adhesion and migration
Natalizumab uses
- MS
- Crohn
- Migraine? (Según clasificación del Dr)
Natalizumab main possible side effect
Reactivation of latent JC virus —> PML
NSAID mechanism of action
Inhibition of COX1 and COX2 = less PGs
(Only irreversible is acetylsalicylic acid)
COX1: constitutively
COX2: mostly CNS
COX2 selective inhibitor
Celecoxib
NSAID ADME
A: rapid oral absorption
D: 95-99% protein bound, wide distribution
M: hepatic biotransformation
E: urine
NSAID uses (5)
- Anti-inflammatory (RA)
- Analgesic
- Antipyretic
- Antiplatelet
- Uricosuric (gout)
Other: PDA closure, mastocytosis, niacin tolerance
NSAID side effects
- GI: ulcers, reflux, pain, diarrhea
- Hepatotoxicity
- CV: COX2 inhibition = thrombosis risk
- Renal: hypotension, nephropathy
- Pregnancy: NOT in 3rd trimester
- NOT 1-3 days before surgery
Paracetamol main side effect
Hepatotoxicity id >4g/day
—> give N-acetylcysteine
Paracetamol ADME
A: oral, IV
D: all tissues except fat
M: CYP2E1 —> NAPQI (toxic metabolite inactivated by glutathione)
E: urine
Which NSAIDS have a higher potency?
Keterolac
Diclofenac - can cause elevated transaminases
Sulindaco relevance as an NSAID
Increased anti-inflammatory activity
Diclofenac ADME
A: oral
D: SYNOVIAL FLUID, 99% protein bound
M: CYP2C
E: urine and feces
Naproxen relevance as an NSAID
Increased half life (9-25 hours)
More potency
Safer for people with CV history
Ketoprofen relevance as an NSAID
Small half life (1-3 hours)
—> Quicker effect
Stronger than ibuprofen and diclofenac
Piroxicam and meloxicam type of medication and uses
Enolic acid
- RA
- Osteoarthritis
- Acute pain and inflammation
Medications with some selectivity for COX2
- Celecoxib
- Diclofenac
- Meloxicam
Enolic acid vs NSAID main difference
Enolic acids have a very high half life:
—> piroxicam = 50 hours
—> meloxicam = 15-20 hours
Medication to use in patients with GI risk and why
Celecoxib, there are mostly COX1 receptors in the gastric mucosa
Do NOT give celecoxib to patients with:
High cardiovascular risk
Sulfa allergy
Colchicine mechanism of action
Binds to tubulin subunit —> inhibit microtubule polymerization —> inhibit phagocytosis of urate crystals, neutrophil activation, migration, and degranulation
= ANTI-GOUT AGENT
Colchicine main side effects (5)
- Narrow therapeutic window
- GI symptoms
- Myelosuppression
- Rhabdomyolysis
- Toxicity: renal, cardiac, CNS
Allopurinol mechanism of action
XANTHINE OXIDASE INHIBITION —> xanthine is not degraded into uric acid
= less uric acid
What is the first line agent for reducing uric acid in plasma?
Allopurinol
(Give colchicine before in gout treatment)
When allopurinol is combined with ______, it causes bone marrow toxicity.
Azathioprine
Allopurinol ADME
A: oral, IV
D: no protein binding, water distribution
M
E: urine
Methocarbamol mechanism of action
CNS depressant
- Sedative
- Skeletal muscle relaxation
ACUTE relief
Methocarbamol ADME
A: oral, IV, IM
D: 50% protein bound
M: hepatic
E: urine
What type of medication is acemetacin?
NSAID
Used for osteoarthritis, RA, back pain, post-op pain
Allopurinol
Uric acid decrease
Colchicine
Prevent gout attacks
Diclofenac
NSAID
Stronger than others
Ketoprofen
NSAID
Moderate-severe pain
Meloxicam
NSAID
Very strong, high risk of clots
RA, low GI and renal side effects
Methocarbamol
Muscle relaxant
Naproxen
NSAID
Long duration, safe when heart risk
Piroxicam
NSAID
Better at reducing swollen joints
Sulindac
NSAID
Acemetacin
NSAID
AR and muscular
Celecoxib
NSAID
Lower GI risk
Paracetamol
Analgesic and anti-pyretic
Perphenazine
Anti-psychotic
Scizophrenia
Severe nausea and vomiting
Rizatriptan
5-HT receptor agonist
Migraine
Natalizumab
Mab vs a4 integrin
No leukocyte adhesion
(MS and Crohn)
Zolmitriptan
5-HT receptor agonist 1B and 1D
Acute migraine
Rizatriptan vs zolmitriptan
R: first choice of treatment
Z: first choice for short-term
