I have a health insurance policy in India and I am about to travel to other countries. During the tour , if I incur any expenditure on medical treatment , Can it be claimed from my insurer in India?

Depends on what policy you have - Normally the coverage is in India and only specific policies allow coverage outside India. Please share details of the policy so that i can advice in detail.

I strongly suggest taking a travel insurance when you travel abroad which does cover some exigencies.