I stumbled across Tricomin Restructuring Conditioner ($20) the other day and, in the interests of full disclosure, should say that I haven't tried it myself. However, I've been told that, while it doesn't make hair grow back, it seems to prevent any additional hair loss. Given that the active ingredient is copper peptide, I'm inclined to believe it.
Copper peptide solutions (like Folligen) really do help hair growth (and eyelashes and eyebrows). In Tricomin the copper peptide has been combined with something even more interesting, carnosine. Actually, it took me a while to work that out. You'll notice in the ingredients that 'Triamino Copper Nutritional Complex' is a combination of alanine, histidine and copper peptide. At first, I couldn't find anything good to say about alanine and histidine (both are amino acids) in the context of hair growth or, indeed, much else. And then I discovered that together they make carnosine.
Carnosine is a brilliant antioxidant, which stabilizes and protects the cell membrane. Specifically, as a water-soluble free radical scavenger it prevents lipid peroxidation within the cell membrane. This makes it much more effective than, say, vitamins E and C, which can prevent free radicals from entering the tissues, but have no effect after this first line of defence is broken. I have, however, only seen unsubstantiated references to carnosine's ability to stimulate hair growth.
A helping hand may also be given by wheat protein, which helps the hair retain moisture, and hydrolized keratin, the latter being the protein that makes up skin, nails and hair. Plus there are vitamins A (retinyl palmitate), E (tocopheryl) and D3 (cholecalciferol).
Personally, I could do without the silicone and paraben preservatives. However, I've seen a lot worse and, if you are concerned about aging and thinning hair, this seems to be well worth a look.
Purified Water, Glyceryl Stearate, PEG-100 Stearate, Stearamidopropyl Dimethylamine, Cetyl Alcohol, Propylene Glycol, Stearyl Alcohol, Dimethicone, Triamino Copper Nutritional Complex, (Alanine/Histidine/Lysine Polypeptide Copper HCI), Hydroxyethylcellulose, Panthenol, Aloe Vera Gel, Soydimonium Hydroxypropyl Hydrolyzed Wheat Protein, Hydrolyzed Keratin, Citric Acid, Methylparaben, Fragrance, Disodium EDTA, Propylparaben, Peppermint Oil, Tocopheryl Acetate, Cholecalciferol, Retinyl Palmitate, Vegetable Oil, FD&C Blue #1, D&C Red #33.