The reduced osmolarity oral rehydration salts formulation currently recommended by WHO for cholera and acute watery diarrhoea contains sodium at which concentration?

• A 60 mmol/L
• B 75 mmol/L ✓
• C 90 mmol/L
• D 111 mmol/L

Explanation

Reduced osmolarity ORS contains sodium 75, chloride 65, potassium 20, glucose 75 and citrate 10 mmol/L, giving a total osmolarity of 245 mOsm/L. The earlier full-strength WHO formula had sodium 90 mmol/L and osmolarity 311 mOsm/L, which caused a modest excess of stool output and hyponatraemia risk in some settings, prompting the change. The 245 mOsm/L formula remains effective in cholera while reducing vomiting and stool volume.

Reference: Park's Textbook of Preventive and Social Medicine, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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