Both topical Minoxidil and Minoxidil pills are both quite effective. Topical minoxidil does not carry the systemic side effect risks as the oral route, however, topical application can lead to its own unique risks, namely allergic dermatitis to the preservatives that are commonly added to the preparations. To avoid this common reaction with topical minoxidil, Blends™ topicals are all propylene glycol and preservative free. To reduce the risks of adverse effects of oral minoxidil, Blends™ uses low dosages which most people tolerate very well. It's worth noting that both topical Minoxidil and oral Minoxidil containing pills can be used together for best results.