**Question:** True about concentration of Oral Rehydration Solution is: March 2007

**Core Concept:** Oral Rehydration Solution (ORS) is a solution used for rehydrating patients suffering from dehydration due to diarrhea. It is a balanced solution containing essential electrolytes and glucose to restore fluid and electrolyte balance in the body.

**Why the Correct Answer is Right:** ORS is a well-balanced solution designed to replace the lost electrolytes and fluids through diarrhea. The concentration of ORS is carefully formulated to achieve the following:

1. **Option D:** Contains an appropriate amount of sodium (Na+) and potassium (K+) ions to replace the lost electrolytes in diarrhea.
2. **Option C:** Provides an appropriate concentration of glucose to act as a source of energy for the body and stimulate the absorption of water and electrolytes in the intestines.
3. **Option B:** Maintains the osmotic gradient necessary for water absorption in the intestines by ensuring the right balance of ions and glucose.

**Why Each Wrong Option is Incorrect:**

1. **Option A:** An incorrect ORS concentration may lead to excessive fluid absorption, causing fluid overload and worsening the patient's condition.
2. **Option A:** An incorrect ORS concentration may result in inadequate electrolyte absorption, leading to electrolyte imbalances and further complications.
3. **Option A:** An incorrect ORS concentration could disrupt the osmotic gradient, hindering water absorption from the intestines, and worsening the patient's condition.

**Clinical Pearl:** The correct concentration of ORS is crucial for effective rehydration therapy. A well-balanced ORS solution helps maintain electrolyte balance, promote water absorption, and prevent complications associated with incorrect concentrations. Always ensure that the ORS solution follows the recommended guidelines for optimal results in treating dehydration caused by diarrhea.