If herbs were a family, I am sure these two would be the husband and wife among them. One is clearly the male, with a powerful presence and a potential to affect the sexual health of the man. While the other, a much feminine presence, with subtle potential to aid with female sexual health and problems.
Ashwagandha helps men gain power and improve their sexual health. The way of working for Ashwagandha is such that it affects the organ and improve virility. If consumed in powder form it has the potential to show impact within weeks. And if combined with herbs like Mochras or Kholanjan, it doubles its impact and giving long-lasting results. A common favourite of people willing to self medicate (views about which can be read here), Ashwagandha is one of the safest herbs to consume, as it carries a lot of benefits and depending on the age of the consumer, it renders its effects which are useful for the person.
Satawari on the other hand is a saviour of women. It helps them take care of their sexual health. But much like the female body, the ailments concerning are also complicated. Therefore Satawari alone cannot take care of all the problems, but it is definitely a good start. It can help women improve intimate health and giving them comfort.
Thus these two drugs are one of the most commonly used and mentioned drugs, and now you know why. So go ahead and try some. Do consult an Unani Physicain if you are suffering from a problem, and then enjoy the use of these amazing and potent herbs.
Wish you good health!