Pharmacology Flashcards
Medications for the stomach, duodenum, and esophagus
Antacids H2 blockers PPI's Sulcralfate Bismuth Metachlopramide (Reglan) Misoprostol (Cytotec)
Types of Antacids
Aluminum salts
Magnesium hydroxide
Calcium carbonate
MOA of Antacids
Neutralizes gastric acid
Bind bile acids
Inhibit peptic activity
Promote angiogenesis in injured mucosa
Drug Interactions of Antacids
Variety
Can bind with drugs taken at the same time
Many antibiotics
Brand Names for Magnesium Salts
Maalox Alamag Mag-Al Mag-Al Ultimate Mylanta
Magnesium Salt SE
Diarrhea Constipation Abdominal cramps N/V Hypermagnesemia
When should you use magnesium salts with caution?
Renal insufficiency
Brand Names for Aluminum Salts
Acid gone
Gaviscon
When should you use aluminum salts with caution?
Renal insufficiency
Can block absorption of phosphate
Brand Names of Calcium Carbonate
Tums Maalox regular chewable Cclci-Chew Rolaids Chooz Alka-Mints
Indications for Calcium Carbonates
Constipation- excess Ca Bloating Gas N/V Abdominal pain Xerostomia
When should calcium carbonates be taken?
2 hours after other medications
When should you use calcium carbonate with caution?
Renal insufficiency
Types of H2 Blockers
Cimetidine (Tagamet)
Ranitidine (Zantac)
Famotidine (Pepcid)
Nizatidine (Axid)
H2 Blockers Indications
PUD: treatment & maintenance
GERD
Dyspepsia: management
MOA of H2 Blockers
Inhibit acid secretion by blocking histamine H2 receptors
When should you take H2 blockers?
30-60 minutes prior to a meal
SE of H2 Blockers
Thrombocytopenia Neutropenia Anemia Pancytopenia Renal toxicity: rare Hepatic toxicity: rare CNS: rare Cardiac: rare
Rare CNS SE of H2 Blockers
Confusion Restlessness Somnolence Agitation Headaches Dizziness Hallucinations Focal twitching Seizures Unresponsiveness Apnea: renal &/or hepatic failure
Rare Cardiac SE of H2 Blockers
Bradycardia Hypotension AV block Prolongation of QT interval Sinus & cardiac arrest
Unique SE of Cimetidine
Gynecomastia Impotence Polymyositis Interstitial nephritis Multiple drug interactions (P450) Cardiac arrhythmias Hypotension
Absorption of H2 blockers
Well absorbed
Peak concentration within 1-3 hours
Reduced if taken with antacids or PPIs
Type of PPIs
Omeprazole (Prolisec, Zegrid) Lansoprazole (Prevacid) Pantoprazole (Protonix) Esomeprazole (Nexium) Dexlansoprazole (Kapidex) Rabeprazole (AcipHex)
Indications for PPIs
PUD GERD Zollinger-Ellison syndrome NSAID-associated ulcers Eradication of H. pylori infection
MOA of PPIs
Irreversibly bind to and inhibits the hydrogen-potassium ATPase pump on the parietal cell membrane
Parietal cells need to be active
Administered before 1st meal of day
Onset of Action of PPIs
About 1 hours
Peak concentration in 2 hours
SE of PPIs
Diarrhea
Headache
Flatulence (Protonix)
Lowest Potential for Drug Interactions
Pantoprazole (Protonix)
Greatest Potential for Drug Interactions
Omeprazole (Prilosec, Zegrid)
Esomeprozole (Nexium)
Significant drug interaction occurs between clopidogrel and what PPI?
Omeprazole (Prilosec, Zegrid)
Black Box Warning for Omeprazole & Clopidogrel
Clopidogrel efficacy decreased
Can clot easier
Long term administration of PPIs increases incidence of what infections?
C. difficile
pneumonia
Long term administration of PPI’s increases what type of fractures?
Hip
Wrist
Spine
Long term administration of PPI’s increases the malabsorption of what key items?
B12
Magnesium
Iron
Administration of PPI’s
30-60 minutes before first meal of day
30-60 minutes prior to last meal of day (2x/day)
Other Medications to Treat the Esophagus, Stomach, and Duodenum
Sulcralfate (Carafate)
Bismuth (Pepto-bismol)
Misoprostol (Cytotec)
MOA of Sucralfate (Carafate)
Stimulates angiogenesis and formation of granulation tissue likely due to growth factor binding
When should sucralfate be administered?
30-60 minutes prior to meals
Cautions of Using Sucralfate
Do not use with aluminum containing antacids or citrate containing compounds
MOA of Bismuth
Inhibition of peptic activity but not pepsin secretion
Bind to ulcer craters
Recruits macrophages to ulcer
May increase mucosal prostaglandin production & mucus bicarbonate secretion
Misoprostol (Cytotec) Indications
Prevention & treatment of NSAID induced ulcers
Pregnancy Category of Misprostol
Category X
Black Box Warning for Misoprostol
May cause abortion, birth defects, or premature birth
Prokinetic Medication
Metaclopramide (Reglan)
Indications for Metaclopramide (Reglan)
Gastroparesis
MOA of Metaclopramide (Reglan)
Improves gastric emptying by increasing gastric astral contractions & decrease postprandial funds relaxation
Metaclopramide SE
Anxiety Restlessness Depression Hyperprolactinemia QT prolongation Dystonia Tardive dyskinesia
Dangerous Drug Interactions with Metaclopramide
Antipsychotics Droperidol (Inapsine) Promethazine (Phenergan) Tetrabenazine (Xenzine) Trimetazidine (Vastarel MR) SSRI's TCAs Atovaquone (Mepron) Metyrosine (Demser)
Types of Antiemetics
Anticholinergics
Antihistamines
Dopamine receptor antagonists (Phenothiazines, benzamides)
Sertonin antagonists
Neurotransmitter receptor sites involved in vomiting reflex
M1-muscarinic D2- dopamine H1- histamine 5-hydroxytryptamine (HT)-3 Neurokinin 1 receptor (NK1)
What receptor does the anticholinergic agents act on?
M1- muscarinic receptor
Main Drug of the Anticholinergic Agents
Scopolamine
Anticholinergic Agent SE
Dry mouth
Drowsiness
Vision disturbance
What receptor does the antihistamines act on?
H1 blockers
What is the primary use for anticholinergic agents?
Motion sickness
What is the primary use for antihistamines?
Motion sickness
Examples of Antihistamines
Diphenhydramine (Benadryl)
Cylizine (Cyclivert)
Dimenhydrinate (Dramamine)
Meclizine (Dramimine-less drowsy)
Antihistamine SE
Sedation
Dry mouth
Vision disturbances
3 Subclasses of Dopamine Receptor Antagonists
Phenothiazines
Butyrophenones
Benzamides
Examples of Phenothiazines
Prochlorperazine (Compazine)
Promethazine (Phenergan)
Examples of Butyrophenones
Antipsychotics
Examples of Benzamides
Metachlorpramide (Reglan)
Trimethobenzamide (Tigan)
Phenothiazines
Antagonistic properties at D2, H1 & M1
Oral, rectal, IV
SE of Phenothiazines
Dystonia Tardive dyskinesia Hypotension Sedation Drowsiness Dry mouth Urinary retention Blurred vision
What can acute dystonia be treated with?
Diphenhydramine
Precautions with Phenothiazines
Elderly With other CNS depressants Poorly controlled seizures Severe liver dysfunction Confusion Delirium
What receptors do benzamides interact at?
Central & peripheral D2
5-HT3
MOA of Metachlopramide (Reglan)
Stimulates cholinergic receptors on gastric smooth muscle cells & enhance acetylcholine release at neuromuscular junction
MOA of Benzamides
Works centrally in area of the medulla oblongata
Serotonin 5-HT3 Antagonists
Mediated medially through central 5-HT3 receptor blockage in vomiting center & chemoreceptor tiger zone blockade of 5-HT3 receptors
Clinical Uses of Serotonin 50HT3 Antagonists
Postoperative & chemotherapy induce N/V
Most cases of N/V except in vertigo
Common SE of 5-HT3 Receptor Antagonists
Headache
Dizziness
Constipation
Examples of 5-HT3 Receptor Antagonists
Ondansetron (Zofran)
Granisetron (Kytril)
Dolasetron (Anzemet)
Palonosetron (Aloxi)
Who is odansetron (Zofran) approved for?
Children
Adults
Pregnancy Category of odansetron (Zofran)
B/C
Drug Interactions with odansetron (Zofran)
Serotonin syndrome
QT prolongation
Monitor LFTs
Con of using odansatron (Zofran)
Expensive
Differential Diagnosis of N/V
Medications/toxicities Infections (GI, ear) Gut disorders CNS causes Endocrine Post-operative Cardiace Radiation
Recommended Antiemetic for Migraine Headache
Metoclopramide (Reglan)
Prochlorperazine (Compazine)
Metoclopramide
Serotonin antagonists
Recommended Antiemetic for Vestibular Nausea
Antihistamines
Anticholinergics
Recommended Antiemetic for Pregnancy-induced Nausea
Ginger
Vitamine B6
Recommended Antiemetic for Gastroenteritis
Dopamine antagonists
Serotonin Antagonists
Prevention of Post-op N/V
Serotonin Antagonists
Droperidol (inapsine)
Dexamethasone
Treatment of Post-op N/V
Dopamine antagonists
Serotonin antagonists
Dexamethasone
Antibiotics for Treatment of Infectious Diarrhea
Ciprofloxacin Norfloxacin Levofloxacin Azithromycin Erythromycin
Symptomatic treatment of diarrhea if no fever or bloody in stool
Antimotility agents
What is best to use to reduce symptoms & treatment of traveler’s diarrhea?
Bismuth subsalicylate (Pepto-Bismol)
MOA of Bismuth subsalicylate
Stimulating absorption of fluid & electrolytes across the intestinal wall
Inhibiting synthesis of prostaglandin responsible for intestinal inflammation and hyper motility when hydrolyzed to ASA
SE of Bismuth subsalicylate
Dark stools
Black tongue
Cautions with Bismuth subsalicylate
Don’t take with other ASA agents
Potentiate anticoagulants
Contraindications to Bismuth subsalicylate
ASA allergy
Infants & children
Symptomatic Treatment of Diarrhea
Loperamide (Imodium)
Diphenoxylate/atropine (Lomotil)
Cholestyramine
MOA of Loperamide (Imodium)
Inhibits peristalsis & prolongs transit time Reduces fecal volume Diminishes fluid & electrolyte loss Demonstrates anti-secretory activity Increases tone on the anal sphincter
Pregnancy Category of Loperamide (Imodium)
C
SE of Loperamide (Imodium)
Abdominal pain Abdominal distention Constipation Dry mouth Nausea Dizziness, drowsiness
MOA of Dipenoxylate/atropine (Lomotil)
Inhibits peristalsis & slows intestinal motility
Inhibits GI propulsion
Prolongs the movement of fluid & electrolytes through the bowel
Pregnancy Category of Dipenoxylate/atropine (Lomotil)
C
When should you avoid Dipenoxylate/atropine (Lomotil)?
Enteroinvasive organism
When should you avoid Loperamide (Imodium)?
Enteroinvasive organism
SE of Dipenoxylate/atropine (Lomotil)
Paralytic ileus, toxic megacolon Drowsiness, dizziness Euphoria Tachycardia Pruritis, urticaria Respiratory depression Anticholinergic effects
Pregnancy Category of Cholestyramine
C
SE of Cholestyramine
Constipation Abdominal pain & bloating Vomiting Excessive flatulence, diarrhea Weight loss Decreased absorption of warfarin, thyroid hormones, digoxin, and thiazide diuretics
Examples of Laxatives
Bulk forming Lubricants & surfactants Saline agents Hyperosmotic agents Stimulants
First Line of Laxatives
Bulk forming
Surfactant agents
Second Line of Laxatives
Saline
Hyperosmotic laxatives
Third Line of Laxatives
Stimulant laxatives
First Line Pharmacotherapy for the Treatment of Constipation
Psyllium (Metamucil): bulk forming agents
Ducosate sodium (Colace): ducosate derivatives
Glycerin: suppository
OTC Bulk Forming Laxatives
Metamucil (psyllium)
Fibercon *Polycarbophil)
Citrucel (methylcellulose)
Benefiber (wheat dextrin)
MOA of Bulk Forming Agents
Softens & lubricates the stool
When does the action of bulk forming agents occur?
Onset 12-24 hours but may take 3 days for full effect
SE of Bulk Forming Agents
Flatulence
Bloating
Abdominal cramping
Excessive use can cause N/V
Contraindications of Bulk Forming Agents
Esophageal strictures GI ulcerations Strictures along GI tract Celiac patients: gluten free formulation Caution in DM
Fibercon Drug Interactions
Decrease absorption of tetracycline & quinolone
Examples of Ducosate Derivatives
Ducosate sodium (Colace) Ducosate calcium (Surfak)
What is the common name of decorate derivatives?
Stool softeners
When should you use surfactant laxatives?
Patients who should not strain with BM
Patients on narcotics
SE of Surfactant Laxatives
Stomach upset
Mild abdominal cramping
Diarrhea
First Line Therapies
Bulk Forming Agents
Decorate derivatives Surfactant laxatives
Second Line Therapies
Phillips Milk of Magnesia
Magnesium sulfate (Epsom salt)
Lactulose
Sorbitol
MOA of Magnesium hydroxide (Milk of Magnesia)
Draws water into bowel through osmosis
Increases intraluminal pressure & motility
When should you avoid magnesium hydroxide?
Renal dysfunction
Elderly
SE Magnesium Hydroxide
GI upset
Diarrhea
When should you use Lactulose or sorbitol?
Failed bulk forming agents & magnesium hydroxide
SE of Lactulose and Sorbitol
GI upset
Diarrhea
Flatulence
Third Line Therapies
Stimulant laxatives Mineral oil Sodium biphosphates Magnesium citrate Castor oil
Examples of Stimulant Laxatives
Senna (Senokot)
Bisacodyl (Dulcolax)
MOA of Stimulant Laxatives
Increase peristalsis through direct effects on the smooth muscle of the intestines
Promote fluid accumulation in the colon and small intestine
Onset of Action of Stimulant Laxatives
15 min-2 hours
SE of Stimulant Laxatives
N/V
Abdominal cramping
Contraindications of Stimulant Laxatives
Surgical abdomen
Fecal impaction
What can be exacerbated by stimulant laxatives?
Rectal fissures
Hemorrhoids
What Medications can be used for a Bowel Prep?
Sodium phosphate
Magnesium citrate (Citroma)
Polyethylene glycol electrolyte solution (Golytely)
SE of Golytely
Sleep disorder Rigors malaise Increased thirst Abdominal distention Pain Anorectal pain Bloating Nausea