Lactulose Medley Pharma (Lactulose)

Lactulose is an osmotic laxative used to treat conditions related to bowel motility and hepatic ammonia accumulation.

• Constipation: softens stool and promotes regular bowel movements.
• Hepatic encephalopathy: lowers blood ammonia levels, improving neurological function.
• Prevention of hepatic encephalopathy after TIPS: reduces risk of recurrent episodes in patients undergoing transjugular intrahepatic portosystemic shunt.

• Lactulose is a synthetic disaccharide that is not absorbed in the small intestine. In the colon, bacterial enzymes hydrolyze it to short‑chain fatty acids, which increase the osmotic pressure within the lumen, drawing water into the bowel and accelerating transit. The acidic environment also converts ammonia (NH3) to ammonium (NH4+), reducing its absorption and lowering systemic ammonia levels.

Lactulose may cause several adverse reactions, ranging from mild to serious.

Common Side Effects

• Diarrhea: loose, watery stools that may occur especially at higher doses, potentially leading to increased bowel movements.
• Abdominal cramping: intermittent stomach pain or discomfort that can accompany increased intestinal activity.
• Flatulence: increased gas production causing bloating and a feeling of fullness.
• Nausea: a sensation of sickness that may precede vomiting, often mild and transient.
• Bloating: a sensation of abdominal distension due to retained gas.

Serious or Rare Side Effects

• Electrolyte imbalance: abnormal levels of potassium or sodium caused by excessive fluid loss, which may affect cardiac function.
• Severe dehydration: marked loss of body water that can result in dizziness, low blood pressure, and requires medical attention.
• Allergic reaction: rash, itching, swelling, or difficulty breathing indicating a hypersensitivity that may need immediate treatment.

When using Lactulose, certain precautions should be observed to ensure safety and effectiveness.

• Assess renal function: evaluate kidney status before initiating therapy, especially in patients with dehydration risk.
• Monitor electrolytes: check serum potassium and sodium levels during prolonged use.
• Adjust dose in hepatic failure: titrate carefully in patients with advanced liver disease.
• Avoid use in intestinal obstruction: contraindicated when bowel blockage is present.
• Use with caution in diabetic patients: monitor blood glucose as lactulose may affect carbohydrate metabolism.
• Store at room temperature: keep in the original container, protect from moisture and direct sunlight.

Lactulose can interact with certain medicines, affecting their absorption or therapeutic effect.

Major Interactions (Avoid)

• Antacids containing magnesium or aluminum can neutralize colonic acidity, reducing lactulose’s conversion to acids and decreasing its osmotic and ammonia‑trapping effects.
• Broad‑spectrum antibiotics (e.g., rifaximin) alter gut flora, which may lessen lactulose’s ability to acidify the lumen and lower blood ammonia.

Moderate Interactions (Monitor Closely)

• Loop or thiazide diuretics combined with lactulose‑induced diarrhea can exacerbate potassium and sodium loss, so electrolytes should be monitored.
• Insulin or oral hypoglycemics may need dose adjustment because lactulose can affect carbohydrate absorption and alter blood glucose levels.
• Oral potassium or sodium supplements may be required to replace electrolytes lost due to increased bowel movements.