As a Nurse Practitioner, you encounter a patient who has accidentally ingested a toxic dose of an organophosphate insecticide. Detail your approach to managing this poisoning using Cholinesterase Inhibitors and Muscarinic Antagonists. Explain the physiological effects of organophosphate poisoning and the reasoning behind your chosen pharmacotherapeutic interventions. In addition, discuss the importance of timely intervention and how the patient’s prognosis might be affected by the chosen treatment plan.