Laxanzien

Laxanzien, often referred to as laxatives, are medicines used to relieve constipation and to prepare the bowel for medical procedures. They work by increasing stool frequency or softening stool, and are selected according to the underlying cause and patient factors.

Classification and mechanisms: bulk-forming laxatives (such as psyllium and methylcellulose) absorb water in the intestine to form a soft, voluminous stool that stimulates movement. Stool softeners (docusate) reduce surface tension, allowing water and fat to penetrate the stool. Osmotic laxatives (lactulose, polyethylene glycol, sorbitol) pull water into the colon to soften and expand the stool. Saline laxatives (magnesium hydroxide, magnesium citrate) also draw water by osmosis and can be electrolyte-containing. Stimulant laxatives (bisacodyl, senna) increase peristalsis and secretion. Newer agents, such as guanylate cyclase-C agonists and chloride channel activators, are used for chronic constipation or irritable bowel syndrome with constipation (IBS-C) under specific guidance.

Indications and precautions: laxanzien are used for constipation, bowel preparation before procedures, and certain slow-transit conditions under medical supervision. They should not be used in suspected intestinal obstruction, undiagnosed severe abdominal pain, or significant dehydration. Use with caution in kidney disease, especially with magnesium-containing products, and in the elderly. Long-term stimulant laxative use may lead to dependence or electrolyte disturbances; drug interactions should be considered.

Availability and use: many laxanzien are available over the counter in various regions. Treatments should start with the lowest effective dose and be paired with adequate fluids and often dietary fiber. If constipation persists beyond a week or is accompanied by weight loss, vomiting, or blood in the stool, medical advice should be sought.