some people say that itching/tightness/inflammation can proceed a period of male pattern baldness. In any case it is cannot be good for scalp health.
Nizoral may help seborrheic dermatitis if you have itching/flaking, and has some anti-androgen properties, so it cant hurt. It can dry the scalp for some people, so use it 3x/week or less and use other more hydrating treatments (t-gell and emu oil have been mentioned) or tricomin spray which fights inflammation and has some hair stimulating properties.
An itchy scalp does not necessarily mean that male pattern baldness is involved. However, with that said, a check-up with an expert in dealing with the scalp and hairloss would be a good idea.