Try Nioxin. I swear by it. I have posted about it a few times on here before. I was losing my hair quite dramatically when I was pregnant with DD2. I was recommended Nioxin so I bought it and in no time the hair loss reduced and my hair was thick & lovely again. My Mum used it when going through chemo and lost little to no hair; actually, she went and had her hair thinned by the hairdresser not long after finishing her chemo!
It is rather expensive, but you do use such small amounts at a time. It is worth every single cent though.

Good luck hun