The number of sessions needed for hyperpigmentation will depend on the severity of the condition, and the treatment you decide on. For milder cases, a few sessions may be sufficient. However, a more significant number of sessions may be necessary for more severe cases. A skin care professional can determine the specific number of sessions needed. It is best to undergo a series of treatments rather than one single treatment. This allows for a more gradual and effective lightening of the skin. Hyperpigmentation can be a difficult condition to treat, but it can be effectively managed with the help of a qualified skin care professional.