Effectiveness of Calcium Channel Blockade for Organophosphorus and Carbamate Pesticide Poisoning - an Open, Pragmatic, 3-arm RCT Repurposing Two Widely Available Licensed Medicines

Effectiveness of Calcium Channel Blockade for OP and Carbamate Pesticide Poisoning


Lead sponsor: University of Edinburgh

Collaborator: Toxicology Society of Bangladesh

Source University of Edinburgh
Brief Summary

This study evaluates whether the addition of intravenous magnesium sulphate or nimodipine to standard therapy (supportive care plus for all patients atropine and, for OP insecticide poisoned patients, pralidoxime) benefits patients after acute anticholinesterase self-poisoning with OP or carbamate insecticides.

Overall Status Not yet recruiting
Start Date June 2020
Completion Date June 2024
Primary Completion Date June 2024
Phase Phase 3
Study Type Interventional
Primary Outcome
Measure Time Frame
Mortality through to hospital discharge, median 1 week
Enrollment 3100

Intervention type: Drug

Intervention name: Magnesium Sulfate

Description: Treatment in addition to standard therapy

Arm group label: Magnesium sulfate

Intervention type: Drug

Intervention name: Nimodipine

Description: Treatment in addition to standard therapy

Arm group label: Nimodipine



Inclusion Criteria:

- Patients aged 16 years or older with suspected OP or carbamate insecticide self-poisoning admitted to medical wards with the cholinergic toxidrome requiring atropine.

- Diagnosis will be made on the basis of the cholinergic toxidrome clinical features (eg. small/pinpoint pupils, bronchorrhoea, sweating) or on the history of atropine administration with beneficial effect. The insecticide involved will be identified where possible from the history, the bottle brought in by the patient or relative, the patient/relative identifying the pesticide on a chart showing all locally available pesticides, and/or relatives sending a photo of the bottle by eg. WhatsApp.

- Patients who ingest combination products containing OP or carbamate insecticides will also be included.

- Inhibited blood cholinesterase activity as shown by routine clinical bedside test

Exclusion Criteria:

- Children aged <16 years.

- Patients who do not require atropine and have not had it prior to presentation during this episode.

- Normal blood cholinesterase activity

- Self-reported known pregnancy (as per South Asian practice, no attempt will be made to formally test for pregnancy in the patients due to the issue of confidentiality in the acute care situation in these hospitals and the social consequences of an unexpected positive response)

- Known occupational and homicidal poisoning

- Past medical history of severely impaired renal function

- Hypersensitivity to magnesium and its salts

- Patients who have had a myocardial infarction or unstable angina in the last month

- Patients with traumatic subarachnoid haemorrhage

- Lack of informed consent (unaccompanied unconscious patients and others)

Gender: All

Minimum age: 16 Years

Maximum age: N/A

Healthy volunteers: No

Overall Contact

Last name: Michael Eddleston, ScD

Phone: 01312426776

Email: [email protected]

facility contact Chittagong Medical College Aniruddha Ghose, MD +8801711068841 [email protected]
Location Countries


Verification Date

May 2020

Responsible Party

Responsible party type: Sponsor

Has Expanded Access No
Condition Browse
Number Of Arms 3
Arm Group

Arm group label: Control

Arm group type: No Intervention

Description: Standard therapy

Arm group label: Magnesium sulfate

Arm group type: Active Comparator

Description: Standard therapy plus magnesium sulfate

Arm group label: Nimodipine

Arm group type: Active Comparator

Description: Standard therapy plus nimodipine

Acronym CCBOC
Patient Data Yes
Study Design Info

Allocation: Randomized

Intervention model: Parallel Assignment

Primary purpose: Treatment

Masking: None (Open Label)

Source: ClinicalTrials.gov