FR Review 4 - Respiratory, GI, Narcotics, and NSAIDs Flashcards
Differentiate the management of dry cough vs wet cough.
Dry: suppressed only if it is exhausting the patient
Wet: never suppressed
What drug class is the mainstay of asthma treatment and how do they act?
Glucocorticoids –> reduce bronchial hyperactivity and inflammation.
By what routes are glucocorticoids administered and which formulation is hydrophilic and why?
PO, IV, and Inhalation –> Inhaled steroids are hydrophilic so the drug stays where you put it.
What is a significant AE of inhaled glucocorticoids and why does this occur?
Thrush (candida) –> the inhaled steroid stays on the tongue and the patient doesn’t gargle.
What is the mechanism of action of Cromolyn and Nedocromil and by what route are they administered?
Mast cell stabilizers - reduce HST on exposure to allergens. Administered by inhalation only.
What is albuterol used for?
Short acting B-2 agonist used as a rescue agent
What is the result of administering a parasympatholytic in respiratory disease and which disease is it most used for?
Bronchodilation - used primarily in COPD and can be an adjunct in asthma
List two anti-cholinergic agents used in respiratory disease and which is used more frequently?
Ipratropium - used more frequently
Tiotropium - long acting agent
What class of drugs is a second-line agent in the management of asthma and what are their AEs?
Leukotriene Receptor Antagonists (Montelukast) - relatively few and benign AEs
What is the mechanism of PDE-4 inhibitors?
PDE-4 chews up cAMP in the lungs. PDE-4 inhibitors increase cAMP which result in bronchodilation.
What is the primary indication for PDE-4 inhibitors?
COPD –> chronic bronchitis, NOT emphysema
What are the instructions to use a MDI?
shake –> exhale –> slowly inhale and activate the MDI
What medication class causes ulcers and state three reasons why?
NSAIDs - because they are acidic, decrease mucus, and they anti-coagulate.
Describe the mechanism of action of sucralfate.
Not absorbed PO - it binds to the ulcer site like a band-aid and protects it from acid.
What drugs will sucralfate interact with?
Tetracyclines and Fluoroquinolones because sucralfate has aluminum in it and the other drugs are chelators.
What cells in the stomach produce acid and what are two common pathways by which they are stimulated that we may antagonize pharmacologically?
Parietal cells stimulated by H-2 (histamine) receptors and the proton pump.
Name 4 H-2 receptor antagonists.
Cimetidine, Famotidine, Nizatidine, Ranitidine.
Are H-2 receptor antagonists available by Px or OTC?
Both depending on dose.
If taking only one H-2 receptor antagonist per day, when should it be taken and why?
At night - most stomach acid is produced at night.
What are three AEs of H-2 receptor antagonists?
Thrombocytopenia
Confusion (especially in elderly or other patients in which the drug may accumulate)
Renally eliminated –> can’t use if CrCl < 50
What 4 drugs will H-2 receptor antagonists interact with and why?
Digoxin, itraconazole, iron, atazanavir - these drugs need acid to be absorbed. H2RAs increase pH.
Name five proton pump inhibitors.
Omeprazole, Esomeprazole, Lansoperazole, Rabeprazole, Pantoprazole.
T/F: PPIs act faster than H2RAs.
False: PPIs are slow on, slow off.
What are prokinetic agents and what are they used for?
Increase peristalsis - used as an anti-emitic, GERD, gastroparesis, facilitate feeding tube placement to get it past the pyloric valve.
Define gastroparesis and what patients get it?
Decrease peristalsis from GI neuropathy - common in DM patients.
What is the father of prokinetic agents and what are its effects?
Metoclopramide - enhances upper GI smooth muscle response to Ach enhancing GI motility and increased gastric emptying. Also blocks dopamine receptors in the chemo trigger zone (vomit center in CNS).
What chronic disease may be exacerbated by metoclopramide use and why?
Parkinson’s because it blocks dopamine in the CNS.
List two salts included in antacids and what is the major AE associated with each?
Al - constipating
Mg - diarrhea
What drug commonly mixed with an NSAID can be used in prevention of ulcers?
Misoprostol - PG that stimulates production of mucus in the gut.
What is the brand name of misoprostol by itself and what is the name of its coformulation?
Cytotec - misoprostol by itself
Arthrotec - misoprstol plus diclofenac
What are the two main AEs associated with misoprostol?
Diarrhea and uterine contractions
What are three agents used to manage constipation?
Magnesium
Lactulose - draws water to it
Polyethylene glycol - draws water to it
Differentiate propylene glycol from polyethylene glycol from ethylene glycol.
Propylene Glyc - diluent used to force drugs into solution that would otherwise not dissolve
Polyethylene Glyc - used in colonoscopy prep
Ethylene glycol - antifreeze
How is diarrhea caused by antibiotics managed?
If typical diarrhea - no management
If C. Diff - treat with PO Vancomycin
What agents can be used as anti-diarrheals?
Codeine - not commonly used bc it is C-5
Lomotil - combo of diphenoxylate (anti-motility) and atropine (anti-ach that slows peristalsis)
Loperamide
What agent is used to treat irritable bowel syndrome?
Dicyclomine - Anti-spasmodic anti-Ach agent specific to the colon.
What are the classes of drugs used as anti-emetics? What is their MOA? Give an example of each.
- Antihistamine - meclizine and dimenhydrimate
- Phenothiazines - dec vomit center activity - prochlorperazine
- Serotonin 3 receptor antagonists - serotonin 3 in brain stimulates N/V - ondansetron
- Prokinetics - inc peristalsis - metoclopramide
- Benzos - MOA unknonwn - lorazepam
- Cannabinoids - pharm grade THC - dronabinol
- Steroids - brain tumor and TBI induced N/V - dexamethasone (most lipophilic steroid)
- Substance P receptor blocker - P receptor agonism causes pain - aprepitant
Which narcotic medication is often given with ampho B to treat the rigors (tremors) caused by ampho B?
Meperidine
What is the antidote for narcotics and what is the potential adverse effect?
Naloxone - may cause acute withdrawal
List and describe the three drugs used to ween addicts off of narcotics.
- Naltrexone: Long acting form of naloxone that reduces euphoria in stable addicts.
- Methadone: Very long acting narcotic with large Vd.
- Bupenorphine: Opioid agonist/antagonist
What drug, related to naltrexone, is used for opioid induced constipation?
Methylnaltrexone
What chemical is the precursor to inflammatory mediators discussed in the NSAID section and what pathway leads to each inflammatory mediator?
Arachadonic Acid (AA)
AA –> COX-1 and CPX-2 –> Prostaglandins
AA –> LO enzyme –> Leukotrienes and Bradykinin
What is the mechanism of action of NSAIDs?
Blocks COX-1 and COX-2 pathways inhibiting production of prostaglandins.
Describe the pathophysiology of an “allergy” to NSAIDs.
Some people make excess leukotrienes and bradykinin in response to NSAIDs. Overproduction of bradykinin induces angioedema.
What are the “three As” of NSAIDs’ mechanism of action?
Anti-inflammatory
Antipyretic
Analgesic
Where are COX-1 and COX-2 enzymes primarily found?
COX-1 in the gut
COX-2 in the periphery
Describe how NSAIDs affect the renal system.
PGs maintain patency of the afferent arteriole. NSAIDs constrict the afferent arteriole and reduce GFR –> causes an increase in serum creatinine.
What is the primary sign of ASA overdose and why?
Tinnitus - NSAIDs increase the level of arachadonic acid which irritates the auditory nerve.
What is the indication for IV indomethacin and by what mechanism? What other drug can be used for this indication?
Indication for patent ductus arteriosis –> PGs keep things open, indomethacin inhibits PGs. May also use IV ibuprofen (ibuprofen lysine).
What is unique about meloxicam and what is the clinical effect of this characteristic?
The most Cox-2 selective of all non-selective NSAIDs. It stays in the periphery and has less GI AEs. Good choice for osteoarthritis in the elderly.
By what routes is ketorolac administered and what is the maximum time it can be used and why?
PO and IM (only IM NSAID) –> max PO use is 5 days because it causes renal toxicity after 5 days.
What is the only Cox-2 selective NSAID still on the market and why is it rarely used?
Celecoxib –> rarely used bc of cost and worry for increased cardiovascular morbidity and mortality.
What are the effects of acetaminophen?
Antipyretic and analgesic (poor antiinflammatory)
What is true about the distribution of acetaminophen and how is this clinically relevant?
Highly lipophilic meaning it will enter the CNS with few effects on the periphery.
T/F: Acetaminophen acts as an anti-platelet
False –> no effect on platelets
What differentiates APAP from the NSAIDs in terms of its metabolism and what is the clinical relevance?
It is metabolized by the liver where most NSAIDs are metabolized renally. APAP toxicity causes hepatotoxicity.
What is the antidote for APAP overdose?
N-acetylcysteine (NAC)
What are the effects of ASA that cause patients to be at increased risk for developing peptic ulcer disease?
It is an acid.
It decreases mucus production in the stomach.
It is an anti-platelet medication.
