Caesalpinia crista, also known as "Fever Nut" or "Karanjwa," is traditionally used in various Ayurvedic and Unani systems of medicine, particularly in India and neighboring regions. Historical texts and ethnobotanical surveys document its use for supporting male reproductive health, including as an aphrodisiac, to improve vitality, and to manage conditions such as sexual debility and infertility. The seeds, in particular, have been mentioned in Ayurvedic classics for their purported ability to "strengthen" the male reproductive system.

Despite these traditional uses, the scientific evidence supporting these claims is limited. Some animal studies have indicated that extracts of Caesalpinia crista seeds may enhance spermatogenesis and testosterone levels in rodents, but these studies are few, often preliminary, and not widely replicated. Systematic clinical trials in humans are lacking. The proposed mechanisms of action are largely speculative and based on in vitro or animal data, such as possible antioxidant activity or influence on steroidogenesis.

In summary, the use of Caesalpinia crista for male reproductive health is primarily rooted in traditional practices, with only minimal and preliminary scientific support. Its efficacy and safety for this indication have not been established by rigorous clinical research.