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: We herein describe the case of an 81 - year - old Japanese woman with neuroleptic malignant syndrome that occurred 36 days after the initiation of combination therapy with tiapride ( 75 mg / day ) and tetrabenazine ( 12 . 5 mg / day ) for Huntington ' s disease .
### Output Text:
We herein describe the case of an 81 - year - old Japanese woman with neuroleptic malignant syndrome that occurred 36 days after the initiation of combination therapy with <span class="chemical">tiapride</span> ( 75 mg / day ) and <span class="chemical">tetrabenazine</span> ( 12 . 5 mg / day ) for Huntington ' s disease . 