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: Galanthamine hydrobromide , an anticholinesterase drug capable of penetrating the blood - brain barrier , was used in a patient demonstrating central effects of scopolamine ( hyoscine ) overdosage .
### Output Text:
<span class="chemical">Galanthamine hydrobromide</span> , an anticholinesterase drug capable of penetrating the blood - brain barrier , was used in a patient demonstrating central effects of <span class="chemical">scopolamine</span> ( <span class="chemical">hyoscine</span> ) overdosage . 