In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: To examine the relationship between quantitative stimulant drug levels , catecholamines , and psychotic symptoms , nineteen patients in a psychiatric emergency service with a diagnosis of amphetamine - or cocaine - induced psychosis were interviewed , and plasma and urine were collected for quantitative assays of stimulant drug and catecholamine metabolite levels .
### Output Text:
To examine the relationship between quantitative stimulant drug levels , <span class="chemical">catecholamines</span> , and psychotic symptoms , nineteen patients in a psychiatric emergency service with a diagnosis of <span class="chemical">amphetamine</span> - or <span class="chemical">cocaine</span> - induced psychosis were interviewed , and plasma and urine were collected for quantitative assays of stimulant drug and <span class="chemical">catecholamine</span> metabolite levels . 