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: Five patients with idiopathic generalized epilepsies ( IGE ) treated with lamotrigine ( LTG ) experienced exacerbation or de novo appearance of myoclonic jerks ( MJ ) .
### Output Text:
Five patients with idiopathic generalized epilepsies ( IGE ) treated with <span class="chemical">lamotrigine</span> ( <span class="chemical">LTG</span> ) experienced exacerbation or de novo appearance of myoclonic jerks ( MJ ) . 