Salaam you responded to my first question but when you say najis do you mean if it has alcohal in it or impure product? Please see previous question and answer below Hair Thickening Spray
Q: Salaam, i just wanted to know if it is permissible to use black hair thickening spray to cover visible scalp areas due to my thinning Hair?
A: Wa alaykum salam If the spray you are talking about is not known to be najis, then you are allowed to use it as long as it does not prevent the water of wudhoo and ghusl to reach the hair and scalp. Sukaina Taqavi