PPIs are one the most commonly used drugs now a days, lets learn some important and interesting facts about Proton Pump Inhibitors (PPIs)

(1) Proton Pump Inhibitors are the most effective drugs for inhibiting the gastric acid secretion. They act by inhibiting H+K+ ATPase (Proton Pump) present in Gastric Parietal cells and this inhibition of proton pump is irreversible.

(2) Drugs in this group are – Omeprazole, Pantoprazole, Esomeprazole, Rabeprazole, Lansoprazole, ilaprazole etc. These drugs are Prodrugs.

(3) These are drug of choice in –

a. Peptic Ulcer Disease (due to any etiology)

b. Gastroesophageal reflux disease (GERD)

c. Zollinger Ellison Syndrome

(4) The PPIs are given empty stomach (One hour before food) and the reason are-

• When drug reaches at its peak level then at the same time, it will get the highest active proton pumps to act.
• Bioavailability of all PPIs are reduced by food, so by taking before food, we can improve bioavailability .

(5) These are very safe drugs and are well tolerated with minimal side effects.

These drugs have shown no harmful effects during pregnancy in humans, but have shown to be harmful in rodents, and despite showing the advice to avoid PPIs in pregnancy by the manufacturers, they are often prescribed during pregnancy.

Loose stools, headache, abdominal and joint pain can be feel by few.

On long term use (in years), they can cause Vitamin B12 and calcium deficiency due to their reduced absorption.

Now some more interesting facts about PPIs-

HIT & RUN drugs – As all PPIs have plasma t1/2 of 1-2 hours, but they inhibit the proton pump irreversibly and hence achieve the inhibition of acid secretion which lasts for 2-3 days (long after the drug is execrated hence, Hit & Run drugs)

• All PPIs are available orally, while Pantoprazole and Esomeprazole can be given IV .
• Oral PPIs are available as Enteric coated or delayed release form to protect them from molecular transformation in the acid in the stomach.
• Though PPIs act on parietal cell of stomach, they are weak bases and absorbed from the intestine.

Hope this post will help you to understand the PPIs more clearly………all the best

Q. Why lactulose is used in hepatic coma patients?

Well, as we are aware that in hepatic coma patient there is failure of liver.

Normally, colonic bacteria produces NH3 which is converted into urea by the liver. This urea is execrated by the kidneys.

During hepatic failure the detoxification of the NH3 does not occur. This NH3 is easily absorbed in the blood and can cause hepatic encephalopathy.

When we give lactulose to this patient (given orally 20 gm or more, three times a day), lactulose is further converted into lactic acid and acetic acid in gut.

This acid medium decreases the PH of the gut and and the NH3 produced by the colonic bacterial flora is converted into NH4+ (polar ammonium ion) which is not absorbed.

In short we can say that lactulose if given in hepatic coma patients, prevent the encephalopathy caused due to NH3 by converting it into its non absorbable form NH4+ .

As now we can understand that lactulose dose not cure the problem, but can be helpful in improving the mental status.

Some other interesting points about Lactulose–

It is a semisynthetic disaccharide made up of fructose and lactose.

It is neither digested nor absorbed in the small intestine.

It is commonly used in the constipation. when taken 10 gm or more with plenty of water, it produces soft stools (it retains water and when broken by bacteria, it become osmotically more active ).

Hope this post is helpful to you in understanding the concept.