Trimethoprim belongs to the gastrointestinal antispasmodic drugs, by reducing the function of gastrointestinal muscle contraction, can be achieved to treat the problem of fast intestinal peristalsis. Trimethoprim acts on the synapse to inhibit the release of acetylcholine and change the state of muscle contraction; it acts on the adrenergic receptor to change the release of norepinephrine, thus relieving the contractile function of the smooth muscle of the digestive tract, regulating gastrointestinal motility, and alleviating the gastrointestinal peristalsis. When patients have intestinal cramps, severe diarrhea, bowel sounds and other fast intestinal motility, they can take Trimethoprim appropriately. When patients before the use of Trimethoprim, must consult the physician, under the guidance of the physician for the use of medication, not to choose the dose of medication and medication time.