Writer Chris Kilham, who calls himself a medicine hunter and is the author of "Tales from the Medicine Trail," published by Rodale Press, set off on an adventure to locate natural herbs that restore sex drive and found that other cultures have been solving the problem for hundreds, if not thousands, of years.

[Editor's note: While natural herbs can have many positive effects on your health, including restoring or improving your sex drive, you should discuss the use of specific herbs with your doctor. Most herbs are safe on their own but your doctor can help you know if they can have potential adverse interactions with other medications you may be taking or other health conditions you have.]

Woody Allen's late 1970s film Love and Death was eerily prophetic, if in name alone, about the Viagra dilemma. The drug enables many men to achieve an erection and regain lost sexual function, but it can also exact a stiff penalty from users. The Food and Drug Administration has reported dozens of deaths among Viagra users. This seems an unnecessarily severe side effect. Concerns about the drug have spurred interest in effective, natural aphrodisiacs without deleterious side effects.

Responding to this interest, I set off for the Amazon rain forest in search of sex-enhancing plants. I traveled in the company of a Brazilian shaman named Bernie Peixoto, a man skilled in tribal wisdom and the use of plant medicines. There in the world's greatest jungle, we encountered two potent sex-boosting plants with a long history of safe use.

Our flight into Brazil put us into the Amazon city of Manaus, where we met with Antonio Matas, the most highly respected herbalist in that area. Antonio shared stories with us about his decades of healing work using rain-forest plants.