| Indication | For the treatment of peptic ulcer disease, irritable bowel syndrome, pancreatitis, gastritis, biliary dyskinesia, pylorosplasm, and reflex neurogenic bladder in children. |
| Pharmacodynamics | Methantheline is a synthetic quarternary ammonium antimuscarinic used to relieve cramps or spasms of the stomach, intestines, and bladder. It can be used together with antacids or other medicines, such as H2-receptor antagonists, in the treatment of peptic ulcer. Methantheline inhibits muscarinic actions at postganglionic parasympathetic neuroeffector sites. |
| Mechanism of action | Methantheline inhibits the muscarinic actions of acetylcholine on structures innervated by postganglionic cholinergic nerves as well as on smooth muscles that respond to acetylcholine but lack cholinergic innervation. These postganglionic receptor sites are present in the autonomic effector cells of the smooth muscle, cardiac muscle, sinoatrial and atrioventricular nodes, and exocrine glands. Depending on the dose, anticholinergics may reduce the motility and secretory activity of the gastrointestinal system, and the tone of the ureter and urinary bladder and may have a slight relaxant action on the bile ducts and gallbladder. |
| Absorption | Rapidly absorbed. |
| Volume of distribution | Not Available |
| Protein binding | Not Available |
| Metabolism | Hepatic, by enzymatic hydrolysis. |
| Route of elimination | Not Available |
| Half life | Not Available |
| Clearance | Not Available |
| Toxicity | Symptoms of overdose: blurred vision (continuing) or changes in near vision, clumsiness or unsteadiness, confusion, convulsions, difficulty in breathing, muscle weakness (severe), or tiredness (severe), dizziness, drowsiness (severe), dryness of mouth, nose, or throat (severe), fast heartbeat, fever, hallucinations, slurred speech, unusual excitement, nervousness, restlessness, or irritability, unusual warmth, dryness, and flushing of skin. |
