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40 Cards in this Set
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- Back
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Docusate
Mineral oil |
Stool surfactant Laxatives(stool softeners)
Require 1-3 days for effectiveness. Decrease surface tension of the stool to allow water and lipids to enter and soften stools. Docusate: used orally or for enema Mineral oil: only laxative approved for fecal impaction in infants or debilitated adults. Side effects: decreases abs of fat soluble vitamins, anal leakage, lipid pneumonitis from aspiration (do not take before bed) |
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Dietary Bran, Psyllium, Methylcellulose and Polycarbophil
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Bulk Forming Laxatives
take 12 hrs - 3 days (not useful rapidly). Are 1st approach for most constipation since mimic normal physiological evacuation. Plants: Dietary Bran Psyllium (can lower serum cholesterol) Synthetic: Methylcellulose Polycarbophil |
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Magnesium sulfate/Sodium phosphate
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Saline Laxatives (Osmotic)
Magnesium sulfate/hydroxide/citrate - activate CCK release to cause fluid retention and increased motility. Sodium phosphate Contain Mg cations/phosphate anions, are RAPID acting 1-3 hrs, activate stretch receptors. If taken too long hypermagnesemia can occur. Caution with renal disease/diuretics |
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Glycerin/Lactulose
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Non digestible sugar and alcohols (osmotic laxatives)
Glycerin - hygroscopic agent and lubricant if given rectally either as a suppository or enema. water retention stimulates peristalsis and produces a bowel mvmt in less than an hour Lactulose - Sorbitol and Mannitol : 1-2 days before effect. Used for constipation due to opioids, vincristine and in the elderly. Also treat hepatic encephalopathy by increasing ammonia excretion. |
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Polyethylene glycol
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Osmotic Laxatives
Highly osmotic alcohol used as a cathartic prior to bowel procedures like endoscopy. To avoid net transfer of ions across wall take with isotonic mixture of Na/K preparations |
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Bisacodyl
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Stimulant laxative = cathartic (unformed). Low grade inflammation which stimulates motility. Alter fluid and electrolyte absorption in intestine. commonly associated with abuse.
Diphenylmethane derivative Requires hydrolysis in bowel for activation and is available as a tablet, enema or suppository.Stimulates sensory nerve endings which stimulate parasympathetic reflexes causing an increase in colon contractions (not small intestine). Bisacodyl is used for the occasional relief of constipation and in bowel cleansing in preparation for x-ray or endoscopic examination. It can cause cramping or excessive fluid secretion |
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Aloe vera
Senna (Ex-Lax) Cascara Rhubarb |
Anthraquinone derivatives: These are plant derivatives that are irritants which cause giant migrating colonic contractions and water and electrolyte secretions.
Long term abuse: pigmentation of colonic mucose (melanosis coli) which is reversible and benign. Overuse might be linked to a condition known as cathartic colon seen in pts (women) with years of laxative abuse. Colon is dilated due to loss of myenteric plexus neurons and muscularis propria atrophy |
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Ricinoleic acid
Lubiprostone |
Ricinoleic acid: castor plant. converted to glycerol and ricinoleic acid in small bowel which stimulates secretion of fluid and electrolytes and increases intestinal motility.
Lubiprostone: stimulates type 2 chloride channel in small intestine increasing intestinal motility within 24 hrs. CIC-2 specific chloride channel activator. Promotes fluid secretion, enhances intestinal fluid secretion to facilitate increased motility. Onset of relief: 57%-63% of patients experience SBM within 24 hrs. Effective for symptoms related to IBS-C. Symptoms including straining, stool consistency, abdominal pain. Effective in both genders, in elderly and young. |
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Methylnatrexone and alvimopan
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opioid receptor antagonists which dont cross the BBB effectively so dont block analgesic actions of opioids but can treat opioid induced constipation. Patients on long term opioid therapy, shorten post operative ileus after bowel obstruction.
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Loperamide
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Opiod agonist
Inhibit the release of Ach from nerve terminals in enteric plexuses, resulting in decreased motility which causes increases in transit time and fecal water absorption. Does not cross BBB so no CNS effects Used for travelers diarrhea and chronic diarrhea. Effects in 3-5 hours and then stop within 48 hours if not working. Adverse: at extremely high doses some CNS depression and paralytic ileus. With active inflammatory disease use caution to prevent the development of toxic megacolon |
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Difenoxin HCl/Diphenoxylate HCl
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Opioid agonists (inhibit Ach release)
Piperidine derivatives. Diphenoxylate is converted to Difenoxin which has the antidiarrheal activity. Difenoxin can enter the CNS more easily than Loperamide and at higher doses can cause significant CNS effects which makes them susceptible for abuse/addiction. Atropine is added to discourage abuse Adverse: toxic megacolon, anticholinergic effects due to added atropine such as dry mouth, blurred vision |
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Clonidine
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Alpha 2 receptor agonists
Leads to increased absorption, decreased secretion, increased transit time. **Special use in diabetics with chronic diarrhea due to autonomic neuropathy who are refractive to other agents. May be effective in treating symptoms associated with opiate, alcohol, and nicotine withdrawal. |
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Cholestyramine, Colestipol
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Bile salt binding agents - diarrhea can be caused by bile malabsorption in the terminal ileum. these agents bind bile acids and bacterial toxins to treat diarrhea
Adverse: bile salt depletion, binds drugs and vitamins, decreases clearance of pathogens |
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Bismuth subsalicylate
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Useful for acid peptic disorders. Useful for diarrhea due to its antisecretory, anti inflammatory, and antimicrobial activity. Can relieve nausea and cramping used for travelers diarrhea, nonsyndromic episodic diarrhea.
Adverse effects: very safe but can cause impaction in infants and debilitated patients. Darkening of stool and tongue is benign and reversible salicylate toxicity |
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Ondansetron
Granisetron Dolasetron |
5-HT3 serotonin receptor antagonists
Anti emetics for stimuli arising from intestinal vagal afferents. Other types of emesis like motion sickness are poorly controlled with these. 1st line agents to treat chemotherapy induced n/v and most effective when given prior to chemotherapy. treat post operative or post radiation n/v |
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Alosetron
Cilansetron |
IBS agents
NOT USED/TESTED!!!!!! |
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Prochlorperazine
Promethazine |
[Phenothiazines]
Dopamine receptor antagonists Promethazine has less affinity for DA receptors and is most useful for emesis due to vestibular dysfunctions, drug induced vomiting, and postoperative vomiting. |
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Droperidol
Haloperidol |
Butyrophenones (Dopamine recep antagonists)
Also antipsychotics, which exert their antiemetic effects through inhibition of central D2 receptors. Droperidol is most widely used antiemetic butyrophenone treatment and has historically been used for postoperative n/v. due to its potent sedative effects it is also used for anestheisa induction and maintenance and as an adjunctive sedative for surgical and endoscopic procedures. Adverse: can produce significant extrapyramidal effects. Also hypotension and rarely prolongation of the QT interval which can lead to ventricular tachycardia and torsade de pointes. |
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Metoclopramide (Part I)
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Metoclopramide (Part I) **TQ - know everything
Substituted Benzamide - Dopamine receptor antagonists, blockade of D2 receptors in the CTZ is the mechanims for this drug (chemoreceptor trigger zone outside the BBB) - Agonist of peripheral 5-HT4 serotonin receptors and is used as a prokinetic agent. Now a 2nd line agent for chemo due to development of serotonin antagonists with fewer side effects Adverse: Parkinsonism, dystonias, restlessness Prokinetic actions from serotonin due to interneurons in the myenteric plexus. |
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Lorazepam
Diazepam |
Antianxiety agents to prevent anticipatory vomiting prior to chemotherapy and vomiting due to anxiety
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benzodiazepines
Diphenhydramine Dimenhydrinate Cyclizine Meclizine Hyoscine |
Antihistamines/Anticholinergics
- Due to the abundance of histaminic and muscarinic receptors in the vestibular system these agents are used primarily for treatment of motion sickness or vestibular dysfunction. Display varying amounts as indicated for receptor types: Diphenhydramine Dimenhydrinate Cyclizine - abdominal cancer Meclizine - vertigo Hyoscine - best for motion sickness, post op nausea Adverse: Sedation, dry mouth, cycloplegia, urinary retention |
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Dicyclomine
Hyoscyamine Glycopyrrolate Methscopolamine |
Antihistamine/Anticholinergics: motion sickness or vestibular dysfunction
IBS: additional muscarinic use for antispasmodic effects in IBD. tertiary:Dicyclomine Hyoscyamine quaternary: Glycopyrrolate Methscopolamine |
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Dronabinol
Nabilone |
Cannabinoids
Major psychoactive chemical in marijuana Antiemetic effects are mediated by stimulation of the CB1 cannabinoid receptor in the CTZ. Can be used in conjunction with other agents like phenthiazines for treatment of chemotherapy induced n/v Adverse: Few, but include dysphoria, sedation, hallucinations, dry mouth, paranoia, increased appetite. withdrawal syndrome can occur |
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Dexamethasone
Methylprednisone |
Corticosteroids
Unknown mechanism but possibly inhibition of peri tumoral inflammation Used with other agents for chemo induced nausea/vomiting, also in IBD |
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Ipecac serum
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Ipecac used to induce vomiting in oral poisoning and acute oral drug overdose. may be abused by people with eating disorders, such as anorexia and bulimia. Induces vomiting by direct stimulatory effect on medullary chemoreceptor trigger zone and works as a GI mucosal irritant.
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Octreotide
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Peptic analog of Somatostatin. Treats diarrhea caused by metastatic carcinoid tumors or VIP secreting tumors, also in AIDS associated diarrhea
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Prokinetics
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Stimulate gut motor function, used for GERD, gastroparesis, postsurgical gastric emptying delays, chronic intestinal pseudo-obstruction and idiopathic constipation
Mechanism: The ENS is composed of a complex network of ganglion cells and nerve fibers located mainly in the submucosa (submucosal plexus), and between the circular and longitudinal muscle layers (myenteric plexus). Primary motor neurons in the myenteric plexus induces smooth muscle contractions through the release of Ach when excited. The activity of this motor neuron is modulated by inputs from other neurons. Nonadrenergic noncholinergic (NANC) neurons and DA neurons inhibit the activation of the motor neurons and cholinergic neurons stimulate the activity of the motor neuron. The activity of each of these modulatory neurons can also be regulated by serotonin released from cells like the ECL cells in the submucosa or by interneurons. |
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Metoclopramide (Prokinetics)
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The prokinetic actions of serotonin are due to interneurons in the myenteric plexus. In the myenteric plexus stimulation of 5-HT3 receptors inhibits motor neuron activity and stimulation of 5-HT4 receptors activates motor neurons and increases GI motility. This can affect both 5-HT3 and 5-HT4 receptors
Metoclopramine is one of the oldest true prokinetic agents and its administration results in coordinated contractions that enhance transit. it has a complex mechanism of action but its effects are largely restricted to the upper GI tract where it increases LES pressure and increases gastric emptying and small intestine contractions. The mechanism is complex but is due to a facilitation of Ach release from myenteric motor neurons. Reduces activity of inhibitory interneurons (5-HT3 antagonism) and increasing the activity of excitatory interneurons (5-HT4 agonism). Central and peripheral antidopaminergic effects. Centrally it blocks D2 receptors in the CTZ and has antiemetic effects. In the periphery it blocks D2 receptors on cholinergic neurons in the myenteric plexus further potentiating the activity of primary motor neurons. Has modest benefit for patients with GERD, gastroparesis or hiccups. Can also be used as an antiemetic. Adverse: Parkinsonism/dyskinesias, Tardive dyskinesia (irreversible) |
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Erythromycin
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Motilin Like Agent
Motilin is a 22 AA peptide hormone found in GI M cells and some ECL cells, and smooth muscle. Activation of motilin receptors on GI smooth muscle promotes the onset of a migrating motor complex resulting in potent upper GI stimulation. Macrolide antibiotics stimulate motilin receptors. |
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Bethanechol
Neostigmine |
Bethanechol - muscarinic agonist which can stimulate M3 receptors on smooth muscle and has been used for the treatment of GERD and gastroparesis. However, due to the multiple cholinergic side effects, cholinomimetics are seldom used for this purpose.
Neostigmine - still used for hospitalized patients with acute pseudo obstruction (ogilvie's syndrome) [AchE inhibitor] |
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Domperidone
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DA receptor antagonist - removed from market
Use metoclopramine, also a DA antagonist, but its a 5-HT4 antagonist |
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Sulfasalazine
Olsalazine Mesalamine |
Aminosalicylates - 1st line for moderate to mild U.C.
Sulfasalazine: 5-ASA + sulfapyridine - In the terminal ileum and colon this is split into 5-ASA (mesalamine) and sulfapyridine by bacteria, 5-ASA is thought to be active. Inhibits production of IL-1, TNF-alpha, inhibits LOX pathway and scavenging of free radicals. Antiinflammatory actionsd of 5-ASA are beneficial but sulfa can cause problems. (contraindicated for sulfasalazine with hypersensitivity to sulfonamide antibiotics or salicylates. |
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Prednisone
Hydrocortisone Methyl-prednisolone |
Glucocorticoids
Result in 60-90% remission in Crohn's disease and 90% remission in U.C. Act by blocking the production of inflammatory cytokines. Adverse: Iatrogenic Cushings syndrome, hypomania, insomnia, acute psychosis |
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Metronidazole
Ciprofloxacin |
Antibiotics
Treat fulminant disease, used successfully in IBD complicated by perianal ulcers and perirectal abscesses and fistuals. Whether the efficacy of these agents is due to the antibacterial properties or some unknown mechanism is not clear. Azathioprine Analog of endogenous purines adenine, guanine, hypoxanthine. Antagonizes mitosis and disrupts DNA/RNA synthesis. Cause a decrease in the proliferation of immune cells and result in a reduced immune response. Used to induce and maintain remission. Can maintain remission in 80% of patients and allow a reduction or elimination of glucorticoids. Adverse: n/v, bone marrow suppression, hepatotoxicity |
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Azathioprine
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Analog of endogenous purines adenine, guanine, hypoxanthine. Antagonizes mitosis and disrupts DNA/RNA synthesis. Cause a decrease in the proliferation of immune cells and result in a reduced immune response. Used to induce and maintain remission. Can maintain remission in 80% of patients and allow a reduction or elimination of glucorticoids.
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Biologics/Anti TNF-alpha Drug names?
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Infliximab
Adalimumab Certolizumab pegol Anti-TNF alpha/Biological response modifers Antibody preparations targeting pro inflammatory cytokine TNF-alpha. 60% symptomatic relief, 30-40% remission rates. Antibodies can develop against the antibodies (ATA) can attenuate or eliminate the response. Adverse reactions to all agents include: serum sickness rnx, severe hepatic rxns leading to fialure, demyelinating disorders, hematologic reactions, CHF, inc risk of lymphoma, rare increased risk of hepatosplenic T cell lymphoma in children and young adults mostly with combined immunomodulator, anti TNF or glucocorticoids. Infliximab chimeric monoclonal antibody against TNF-alpha. Approved for use in patients with IBD who are refractive to traditional therapies. IV infusion. Can promote mucosal healing, closure of fistula, reduces need for streoid therapy. Blocks the production of inflammatory cytokines IL-1 and IL-6 as well as blocks cellular infiltration by leukocytes. Adverse: n/v, headache, abdominal pain, cough, fatigue. Acute infusion reactions. |
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Infliximab
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chimeric monoclonal antibody against TNF-alpha. Approved for use in patients with IBD who are refractive to traditional therapies. IV infusion. Can promote mucosal healing, closure of fistula, reduces need for streoid therapy. Blocks the production of inflammatory cytokines IL-1 and IL-6 as well as blocks cellular infiltration by leukocytes.
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Adalimumab
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Human recombinant monoclonal Ab against TNF-alpha, currently approved for RA and recently approved for Crohn's disease in refractive pts. Potentially fewer side effects than infliximab since all parts of the molecule are of human origin.
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Certolizumab
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This is a recombinant anti-TNF alpha Ab Fab fragment (no Fc) that is 95% human and is conjugated to polyethylene glycol. Without the Fc portion there is no antibody mediated apoptosis, complement activation and cellular toxicity. It is approved for Crohn's disease that is not well controlled with more traditional therapies. SubQ every 2-4 weeks
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Natalizumab
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Anti Integrin
Humanized IgG4 monoclonal antibody directed aginst the alpha 4 subunit of integrins. Integrins allow for leukocytes to bind to vascular endothelium and infiltrate into surrounding tissues. Natalizumab blocks this and is useful for a specific subset of pts refractive to other therapies. high risk of developing progressive multifocal leukoencephalopathy, therefore its use is severely restricted. |
