Rogaine Foam Not Suitable for Women?

Could you please explain why Rogaine foam is unsuitable for women. My daughter, on the recommendation of her dermatologist, was using Rogaine 5% until she developed an allergic reaction (confirmed by an allergy test) to the propylene glycol.

If he suggested Rogaine 5%, why then is the foam, which contains 5% minoxidil, unsuitable?

I believe that the Rogaine Foam does not contain propylene glycol (which is the most allergic component with minoxidil). I don’t see a problem with women using Rogaine Foam, although it is not marketed towards women. I’d expect a Women’s Rogaine Foam to be available at some point with a slightly different formulation (similar to how Rogaine and Women’s Rogaine are the same, yet different).