I use Salvamin (which is a natural cream I found in a specialized herbal shop). It’s used for arthritis, piles, varicose, rheumatism, Raynaud, muscle injuries and other similar conditions. It states it restores the blood flow.
It’s really good, it really increases the blood flow, my flaccid size gets really bigger and the veins get filled with blood, without necessary having an erection. Actually the veins get really visible underneath the skin that gets red. It doesn’t sting or anything, I just get a nice warming sensation. It costs around 2$ for about 2 oz.