Why does drinking milk on an empty stomach cause stomach pain?

Generally, abdominal pain after drinking milk on an empty stomach may be caused by lactose intolerance, excessive gastric acid, gastrointestinal dysfunction, gastroenteritis, or gastric ulcers. Different causes require targeted treatment under a doctor's guidance. It is recommended to seek medical attention promptly for early diagnosis and treatment of discomfort symptoms. Detailed analysis is as follows:

1. Lactose Intolerance: Lactose is the primary sugar in milk. Lactose intolerance occurs due to a deficiency of lactase enzyme, which prevents lactose from being properly broken down. Undigested lactose enters the large intestine, where it is fermented by bacteria, producing gas that leads to abdominal pain, accompanied by bloating, diarrhea, belching, stomach rumbling, nausea, and other symptoms. To manage this, avoid lactose-containing products; alternatively, use lactase supplements or switch to low-lactose or lactose-free milk.

2. Excessive Gastric Acid: Milk is an alkaline food that may stimulate gastric acid secretion, leading to excess acid production and resulting in abdominal pain, along with heartburn, acid reflux, and stomach pain. Avoid drinking milk on an empty stomach; instead, consume it after meals. If necessary, follow a doctor’s instructions to take medications such as esomeprazole magnesium enteric-coated tablets, rabeprazole sodium enteric-coated tablets, or lansoprazole tablets to relieve symptoms.

3. Gastrointestinal Dysfunction: Gastrointestinal motility disorders may impair the digestion and absorption of milk in the digestive tract, causing abdominal pain along with diarrhea and bloating. Follow medical advice to use medications such as Bifidobacterium live powder, mebeverine hydrochloride tablets, or pinaverium bromide tablets to alleviate symptoms.

4. Gastroenteritis: Consuming cold milk, contaminated milk, or expired milk may lead to gastroenteritis, causing diarrhea along with abdominal pain and vomiting. Under medical guidance, consider gentle abdominal massage to promote intestinal motility, or take prescribed medications such as ciprofloxacin hydrochloride capsules, bismuth potassium citrate tablets, or enteritis relief granules to reduce inflammation.

5. Gastric Ulcer: Excessive gastric acid production or infection can damage the gastric mucosa. Milk may irritate the mucosal lining, worsening gastric ulcers and causing abdominal pain, often accompanied by upper abdominal pain, nausea, and vomiting. Avoid drinking milk on an empty stomach. Follow your doctor’s recommendations to use medications such as belladonna tablets, cimetidine tablets, or colloidal bismuth pectin capsules for symptom relief.

If abdominal pain occurs after drinking milk on an empty stomach, consult a doctor to determine the underlying cause and receive appropriate treatment based on the diagnosis. Avoid self-diagnosis and self-medication to prevent delays in proper care.