| Indication | For the reduction of the symptoms of muscle weakness and easy fatigability associated with the myasthenic syndrome of Eaton-Lambert. It is not indicated for treating myasthenia gravis. |
| Pharmacodynamics | Guanidine apparently acts by enhancing the release of acetylcholine following a nerve impulse. It also appears to slow the rates of depolarization and repolarization of muscle cell membranes. |
| Mechanism of action | Not Available |
| Absorption | Rapidly absorbed and distributed |
| Volume of distribution | Not Available |
| Protein binding | Not Available |
| Metabolism | Not metabolized. |
| Route of elimination | Not Available |
| Half life | 7-8 hours |
| Clearance | Not Available |
| Toxicity | LD50 = 475 mg/kg (oral, rat). Can cause severe gastrointestinal symptoms (nausea, vomiting and diarrhea), bone marrow suppression, renal insufficiency and other hematologic abnormalities (anemia, leucopenia). Severe guanidine intoxication is characterized by nervous hyperirritability, fibrillary tremors and convulsive contractions of muscle, salivation, vomiting, diarrhea, hypoglycemia, and circulatory disturbances. |