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: Worsening of Parkinsonism after the use of veralipride for treatment of menopause : case report .
### Output Text:
Worsening of Parkinsonism after the use of <span class="chemical">veralipride</span> for treatment of menopause : case report . 