If I was complaining from hereditary hair loss and started to use topical minoxidil how can I stop it without losing my hair?

Wrong question. First, there is no reason to ever stop unless you are allergic to it. Second, hair does not fall out if it is stopped. Minoxidil is a weak stimulant of hair growth which is effective, if at all, only if it is used religiously for a long time. Naturally, it is effective only when in use. This benefit, if any, is lost when it is stopped. But the hair does not shed if it is stopped.
May not be able to. You can discuss with dermatologist to see what your options are.

Related Questions

Can I use propecia and topical rogaine (minoxidil) together to stop hair loss?

Yes. Yes, you can use both products together to slow down the process of hairloss. Read more...
Yes. The work differently. Propecia acts to diminish the affects of testosterone on the scalp. Rogaine (minoxidil) works to increase the effectively blood flow to the hair follicles. Read more...