Anti-emetics & IBD Tx - Fitz Flashcards
Which drug is a first line therapy for mild/moderate ulcerative colitis, but is INNEFFECTIVE for Crohn’s Disease?
Aminosalicylates!
Which IBD salicylates work in what parts of the GI tract?
Colon only:
Balsalazide, Olsalazine, Sulfasalazine
Small Bowel to Rectum:
Mesalamine
The thing you hate the most about meds are their side effects. How do you feel about the aminosalicylates used for IBS?
You love all the aminosalicylates!
With the exception of one!
Sulfasalazine! (YOU LOATHE IT)
- The sulfa that is cleaved off can cause hypersensitivity reaction and decreased folate absorption
- 40% Gi upset, headache, arthralgia, bone marrow suppression
What corticosteroids are used for moderate to severe Crohn’s?
Prednisone, prednisolone
What is the overall way that corticosteroids and antimetabolites work to treat Crohn’s?
Both work by immune suprression
How is Budesonide work differently that other corticosteroids? USed in what severity of Crohn’s?
It has local rather than systemic effect in the lung and GI tract (oral controlled-release)
It is used in mild-moderate CD involving ileum and proximal colon
Atimetabolites are given in low doses for maintenance and remission of UC and CD. What are three of these drugs?
Azathioprine
6-Mercaptopurine
Methotrexate
How does infliximab work?
It decreases TNF-alpha, which is inappropriately increased in IBD.
Why on earth would you test a patient for Tb before gibing them infliximab?
One of the side effects is reactivating Tb.
Infections can be a big problem because you are targeting a suppressing the immune system
What cancer problem do you have to worry about when treating with infliximab?
Elevated risk of lymphoma
Your 5 year old ingests a very corrosive poison. Your friend rifles through his cabinet and finds some Ipecac. Should you use it?
No!
OTC sales of ipecac are banned,
Administration of ipecac is dangerous is the poison in corrosive, a petroleum distillate, or a rapid-acting anti-convulsant
Most effective agent for treatment of motion sickness?
Scopalamine
You are an oncologist and are administering cisplatin to a patient with small cell lung cancer. Her biggest complain is the nausea. What drug would be MOST effective to reduce emesis?
The “-setrons”
```
5HT3 Antagonists
Dolasetron
Granisetron
Ondansetron
Palonosetron
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What drug is given by transdermal patch to treat motion sickness?
Scopolamine
Its a dopaminergic and muscarinic receptor antagonist in the cerebelleum
How does aprepitant and fosaprepitant work?
- Substance P receptor antagonist
- NK1 receptor antagonist
Aprepitant shouldn’t be given along with chemo drugs like taxels, etoposides, and Vinca alkalods?
Some chemo agents like those listed are metabolized by CYP3A4.
Aprepitant is also metabolized by CYP3A4, so it can really increase side effects like bone marrow suppression in the antineoplastics
What are three of the antihistamines used as antiemetics?
Dimenhydrinate
Diphenhydramine (dramamine)
Meclizine
BY what mechanism do drugs like Droperidol, Metoclopramide, and Prochlorperazine work?
D2 receptor antagonists on the D2 receptors of the CTZ
Name 2 antiemetics drugs (of the same class) that have side effects of euphoria, hallucinations, sedation, dry mouth, and increased appetite:
Dronabinol and Nabilone
cannabinoids
Where is the Chemoreceptive Trigger Zone (CTZ) located?
Be specific:
Located in the Area Postrema on the floor of the 4th Ventricle
REMEMBER: Although the CTZ is in the brainstem, it is found outside the BBB
What treatment is used to bind toxins in the upper Gi?
Activated charcoal
Remember you must give it in a 10:1 ratio
What treatment would you use for decontaminating the colon of an individual who was trying to sneak drugs over the border in his rectum?
Polyethylene Glycol-Electrolyte Solution
Note: Same thing you give people to prep before an endoscopy
2 Weeks after beginning treatment for Ulcerative colitis, a 16 year old girl develops a skin rash and fulminant hepatic failure. Exploratory surgery revealed necrotizing pancreatitis and haptic necrosis consistent with the drug treatment she was on.
What is the drug?
Sulfasalzine!
hate that one…
What is the primary site of action of 5HT3 antagonists with respect to their use as antiemetics?
GI tract!
