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: Can lidocaine reduce succinylcholine induced postoperative myalgia ?
### Output Text:
Can <span class="chemical">lidocaine</span> reduce <span class="chemical">succinylcholine</span> induced postoperative myalgia ? 