The seven primary chakras as they are commonly defined
Soul Manifestation Review begin at the base of the spine and rise to the top of the head. Activation of any one of these without first sequentially activating and cleansing the ones below it will result in an influx of energy that can short-circuit the lower chakras, which aren't ready to process the higher energy. The third eye, being second from the top, should not even be approached until one has their entire system running smoothly.
So before starting any meditation designed to open the third eye, you must objectively and honestly assess your current progress at each of the previous levels.