Nasogastric Tube Flushing Guidelines

Standard Flushing Protocol

The American Society for Parenteral and Enteral Nutrition recommends flushing nasogastric tubes with at least 30 mL of drinking quality water before and after each feeding or medication administration, and every 4 hours during continuous feeding to prevent tube obstruction 1
Flush with at least 30 mL of water before starting and after completion of feeds for bolus administration, as part of routine patient and caregiver education 1
Flush every 4 hours during continuous feeding to maintain NGT patency 1
Flush before, between, and after each medication when administering drugs through the tube, using 30 mL of water for each flush 2

For immunocompromised patients, such as hematopoietic stem cell transplant patients or solid-organ transplant recipients, use sterile water for flushing NGTs if the facility's water supply is contaminated with Legionella 3
Standard drinking quality water is acceptable for immunocompetent patients 1

Never mix medications before administration through the tube, and administer drugs individually with 30 mL water flushes between each medication 2
Adequate flushing technique is more critical than adding agents like heparin to prevent occlusion 2

Do not use inadequate flush volumes—less than 30 mL increases occlusion risk, particularly in small-bore tubes 1, 2