Praise be to Allah.
Allaah has permitted women to adorn themselves for their husbands, and He has permitted them to adorn themselves in front of other women and mahrams, but this adornment is not permissible if it involves anything that goes against sharee’ah. So it is not permissible to apply cosmetics that will cause her physical harm, and it is not permissible for this adornment to involve changing the creation of Allaah. Kohl, henna and the like do not involve changing the creation of Allaah, unlike filing the teeth, plucking the eyebrows and tattoos -- these things do involve changing the creation of Allaah with regard to shape and colour, hence these actions are haraam and are major sins.
It was narrated that ‘Abd-Allaah ibn Mas’ood (may Allaah be pleased with him) said: May Allaah curse the one who does tattoos and the one who has a tattoo done, the one who plucks eyebrows and the one who has her eyebrows plucked, and those who file teeth for the purpose of beautification, changing the creation of Allaah. Narrated by al-Bukhaari (5931) and Muslim (2125).
One of the things that is similar to these haraam actions is that which is mentioned in the question of putting creams to make the lips swell. This is unlike putting colour that is permissible and is not harmful to the lips, because that does not fix a colour permanently like tattooing; rather it is temporary and is no different from the ruling on henna and kohl for the eyes. Hence it seems to us that making the lips larger with these cosmetics is not permissible, because it is changing the creation of Allaah. Even worse than that and more haraam is having surgery to make the lips bigger. Such things are unknown except in the case of weakness and defeatism and blind following of the kaafir west. These women are not content with the way Allaah has created them; rather they have started to tamper with their bodies, making things larger or smaller and seeking beauty in something other than that which Allaah has created. Some of them have become a laughing stock among people when they made their lips so big that they looked like the lips of a camel! This is how people who saw them commented on them.
So the Muslim women should feel proud of her religion and morals and the rulings of Allaah's laws, and she should keep away from imitating kaafir and immoral women. Allaah has permitted her to use many things as adornment and He has not forbidden her anything except that which is harmful to her body, attitude and religious commitment.
In our answer to question number 1006 we have mentioned various kinds of cosmetic surgery and we have stated that among the kinds of such surgery that are haraam is surgery to enlarge or reduce the breasts. This is like the ruling on enlarging the lips, so please refer to this question.
See also the answer to question number 47694.
And Allaah knows best.