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: CAPD is inefficient in removing piperacillin , whereas hemodialysis can rapidly terminate the piperacillin - induced encephalopathy .
### Output Text:
CAPD is inefficient in removing <span class="chemical">piperacillin</span> , whereas hemodialysis can rapidly terminate the <span class="chemical">piperacillin</span> - induced encephalopathy . 