Am on both lexapro (escitalopram) and clonazepam. since the lexapro (escitalopram) should be effective now, can melatonin be used to wean off of clonazepam?

Not necessarily : This is something you and your physician should discuss. The weaning period for Clonazepam is dependent on how long and at what does your were using. Don't do anything without talking it over with your physician! cold turkey withdrawl from Clonazepam can be dangerous.

No: I would talk some more to physician about your plans before implementing them. My concern would be that melatonin would not do anything to prevent the potential seizures that could accompany the discontinuation of clonazepam. Your physician will hopefully guide you through the transition in a way that will minimize rhe risk of seizures. Stay safe!