Laser treatment for dark underarms typically involves the use of laser technology to target and break down excess pigmentation in the skin. The process is known as laser skin lightening or laser skin rejuvenation. During the procedure, the laser emits light that is absorbed by the melanin in the skin, helping to reduce pigmentation and promote a more even skin tone. Multiple sessions may be required for optimal results. It's crucial to consult with a dermatologist or a qualified skincare professional to assess your specific needs, skin type, and eligibility for the treatment. 

For skin whitening of the underarm region, you will mostly be prescribed some exfoliant, a shaving routine, and medicated creams. And for better results, doctors could suggest laser or micro-needling. The broader range would be rs. 2,00 to rs. 2,000, depending on treatment opted for as well as the number of sessions, clinician expertise, clinic location, and infrastructure.
Refer to the following list to find doctors who will provide services at affordable prices - Dermatologists in India.