All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
Using solarium to change one's skin color may occur in two cases:
First: When one suffers from leprosy or any other dermal disease and he needs such a way of medication for treatment. It is permissible to use such medication, unless its side effects are more serious than the disease itself.
Second: When one does not suffer any disease but he wants to change the color of the skin, it is not permissible in this case to use this machine or others, because doing this is included in changing the creation of Allaah. It was narrated on the authority of Ibn Mas‘ood that the Prophet, sallallaahu ‘alayhi wa sallam, said:
Allaah has cursed women who practice tattooing and those who have it done, women who pluck eyebrows (for others) and those who have it done, and women who make spaces between their teeth to beautify themselves, whereby they change the creation of Allaah. [Al-Bukhari and Muslim]
The devil has made a pledge to command all those people who follow him to change the creation of Allaah. Allaah Almighty says in the Quran through the words of Satan (what means): {And I will command them so they will change the creation of Allaah.} [Quran 4: 119]
Allaah Knows best.