[lee-usmle]

Certain tricky clinical scenarios require us to stop specific medications if we are going to do some procedures or in certain circumstances. Such important caveats are usually forgotten in clinical practice and also when we answer USMLE questions.

Here's a list of some of these tricky situations:

• Before starting Iodine treatment for hyperthyroidism stop propylthiouracil (1-2 weeks) as it blocks the uptake.
• Before doing endoscopy for H pylori stop treatment (1-2 weeks) to avoid false negative results.
• Before measuring gastrin level in the diagnosis of ZES you have to stop all PPIs as they decrease acid and falsely increase gastrin level.
• Do PPD before you start the patient on Infliximab as a baseline because it increases the risk of reactivating TB.
• If you plan to do immediate angiography or bypass surgery for an ischemic patient then don't start the patient on clopidogrel in acute coronary syndrome cases as you might risk serious hemorrhages.
• Give 3 weeks anticoagulantion before you electively DC cardiovert an atrial fibrillation as the DC itself has some risk of thromboemolism.
• Don't give the insulin shot prior to ECG exercise test as you will risk inflicting a serious hypoglycemia.
• Stop beta blocker medications prior to allergic desensitization as they block epinephrine which might be needed as an emergency measure during the desensitization procedure.

This is what I gathered in my notes. If you have more please post your replies.

 

[khanar]

Regarding Radio Active Iodine Therapy and Antithyroid medication

Nice post.
But regarding the first point. I think it's wrong. Because what I know is that it's good idea to give antithyroid medication before radioactive Iodine because there's a risk of transient thyrotoxicosis right after RAI therapy (as the gland will be destroyed and will be releasing it's thyroid hormone reserves).

Am not sure :notsure:

 

[Lakshay]

Also clopidogrel is indicated before doing pci ???

 

[dinosaur108]

Stop metformin 48 hr before doing contrast procedures.....and also give NS to prevent kidney damage...

 

[drshaziamirza]

In primary Hyperaldosteronism

initial test iz PARA , early morning sample

drugs that shud be withdrawn 2-3 wkz before testing -
1) Secretin
2) B bloker
3) spironolactone
4) eplerenone