Elderly people who do not have a bowel movement for a month need to consider dietary causes and disease and drug causes. Dietary causes include prolonged bed rest, fine diet, etc.; disease causes include intestinal mass, Crohn’s disease, diabetes, hypothyroidism, etc.; drug causes include calcium ion antagonist, anticholinergic drugs, etc. 1. Dietary reasons: such as long-term bed-ridden elderly, gastrointestinal tract peristalsis function decreased significantly, can cause constipation; such as diet is too fine, food residue is small, can also lead to constipation. 2. Disease causes: such as intestinal mass can also have weakness, weight loss and other symptoms; such as Crohn’s disease can also have abdominal distension, abdominal pain, mucus blood stools and other symptoms; such as diabetes mellitus, hypothyroidism, etc. can lead to intestinal peristalsis decreased, triggering constipation. 3. Drugs: some drugs can inhibit gastrointestinal peristalsis, thus triggering constipation. Such as nifedipine, amlodipine and other calcium antagonists; such as atropine, scopolamine and other anticholinergic drugs. For the reason that the old man does not defecate for a month, it is recommended to consult a doctor to analyze the specific situation.