In general, oil shampoo is good for hair extensions. As we know, hair extensions can be a tricky thing to care for. Therefore, the right shampoo is so important. Permanent hair extensions have a bond element. These hair extensions cannot be washed with shampoos that have sulfates or synthetic oils in the formula as it breaks down the bonds and will have your extensions falling out. After installing hair extensions, you have to wait 72 hours and then wash your hair.