Can you use a permanent hair dye the same day you used a semi permanent hair color?

Yes, actually you can. But I would recommend you use the permanent dye first and then follow up with the temporary color. This is a technique that some hair professionals use when taking a blonde to a deeper shade of color. It will infuse the color deeper and cause the color to be longer lasting. But as a rule, after using the permanent dye... rinse the color out thoroughly (don't condition) and towel dry. Then apply the temporary color (use one that is similar to the permanent hair color you have chosen) and then let process for the designated amount of time. When the hair is done processing, rinse, shampoo and condition. I recommend allowing the conditioner (preferably a good one) at least three minutes to soak in. Then rinse and style as usual.