Annapolis and Anne Arundel County Police Fire were dispatched to the 900 block of Bay Bridge Road for a reported overdose.
At the scene, officials say a patient ingested a powdery white chemical substance. They say the Annapolis Hazmat Team immediately reported to the scene a short time after to investigate the chemical found in the car.
Investigators were able to determine that the chemical was Sodium Azide. They were unable to determine how the patient got a hold of the substance.
The patient remains in critical condition.