SAN ANTONIO, Principe — Viagra is not needed on this island. For erectile dysfunction, herbal healers prescribe a bit of bark to heat until soft, chew and spit out.
The reddish-brown bark from the pausinystalia yohimba, a tree that grows in the closed canopy forests of the Gulf of Guinea, contains a powerful alkaloid (yohimbe) that increases blood flow to the pelvic area. In other words, it has the same effect as Viagra.
This is just one example of the bona fide medicinal value of the rich herbs and vegetation of the West African islands of Sao Tome and Principe. Hypertension, high blood pressure or sprained ankle? The herbal healers have potions to treat them. And new studies are proving that the traditional remedies have scientific medicinal value.
From the air, the islands appear as emerald jewels floating on the blue Atlantic Ocean. Green, dense primal rainforest covers these tiny volcanic islands off the coast of Gabon in West Africa. 
On the ground in Principe, a small man weaves his way through the lush forest. Here and there he stops, whispers words, almost a chant, collects leaves, scrapes bark, or digs up a root.
“Each plant has a spirit. I speak to them. I explain that I come in good faith, to heal, not to do evil,” he says.
Cosme Quaresma Costa, 63, is an stlijon, or traditional healer, in the island's local creole (crioulo) language. For a living, Costa drives a truck for a building company. For healing, the forest is his pharmacy, and medicinal barks, his expertise.
Stlijons are specialized — herbalists, bush surgeons, masseurs, urine analysts, dream interpreters, ventosas, birth attendants or diviners. They treat all kinds of ailments with herbal medicines.
For high blood pressure, the root of rauwolfia vomitoria has been a staple in the African pharmacy for centuries. It contains reserpine, a naturally occurring drug identified in 1952 that became the first modern medicine to treat hypertension.
But the empirical knowledge of stlijons is disappearing as fast as the tropical forest. Many are elderly and have few students.
“These healers hold generations of accumulated knowledge and practice,” said Maria do Ceu Madureira, a professor of pharmacology at the Egas Moniz Higher Institute for Health Science in Portugal.
For the last 15 years, Madureira and a team of pharmacists and biologists worked with 40 respected healers and midwives on Sao Tome and Principe. They noted 1,000 recipes for herbal medicines, identified and classified 325 medicinal plants, and reviewed the existing literature.
In Portugal, lab tests were conducted on 50 plants. Sixteen look promising against ailments ranging from hypertension, arterioescleroris and colon cancer to malaria. Many have proven effects as sedatives and analgesics, others have anti-bacterial, anti-fungal and anti-histaminic properties.
The research is a partnership of Egas Moniz, the University of Coimbra and the Ministry of Health of Sao Tome, funded by the Calouste Gulbenkian Foundation in Lisbon.
Published in 2008, the “Ethno-pharmacological Study of Medicinal Plants of Sao Tome and Principe” is nearly sold out. All profits go to the three stlijons credited as co-authors — among them, Sum Costa. (Sum is the respectful title given to male healers, Sam for a female.)
Ten of Sum Costa’s bark-based medicines feature in the study. Thanks to the book royalties he has been able to renovate his home and he has a $30 monthly stipend.
Together with the government, healers would earn royalties of any drug developed on the basis of their knowledge.
Co-author Sum Lourenco de Sousa Pontes Junior treats malarial patients with tithonia diversifalia, known in Latin America for its anti-diabetes and anti-inflammation properties. This was the first time anti-malarial use had been documented, and lab tests proved Sum Pontes right. “This study marries traditional medicine and science and showcases our plant wealth,” said Dr. Artur Borje, Principe’s chief health officer.
Indeed, the islands are a treasure trove of biological diversity spanning more than 700 botanical species. Of these, 95 are endemic to Sao Tome and 37 to Principe, concentrated in the primary rainforest known as obo.
Other plants were brought from Latin America, Europe, Asia and mainland Africa by the Portuguese, who landed here in 1498 and turned the uninhabited islands into a center for growing sugarcane, coffee and cacao and for the slave trade.
The islands were also a hub for people. Until independence in 1975, the Portuguese brought workers — slaves, forced, indentured and later contracted — from mainland Africa for the plantations.
Sao Tome, the bigger island at 322 square miles, has little obo (primary rainforest) left but plenty of secondary forest.
Principe, at 49 square miles and a population of 1,500, is pure obo, volcanic peaks and sandy beaches. Its capital, Santo Antonio, is a sleepy, quaint place, with pastel-colored houses, steepled churches, friendly people and few tourists.
On a recent Saturday, Borje was chatting on the streets of San Antonio with its famous masseur, Jose Batista da Silva, known as Sum Jeje. Borje sends many patients to Jeje and vows they get better.
Sum Jeje studied for 14 years with older stlijons and passed several exams before practicing.
In Africa, to cure is to restore human vitality and harmony with the universe. Body and soul are not separate entities and they are not isolated from nature, spirits and other people.
This knowledge can’t be hurried. It earns respect, even fear, but little money. Most people on Sao Tome are poor and the healers fees are modest. Healers need to work other jobs to pay the bills. Not surprisingly, few young take up the craft.
“Young people don’t want to spend years studying, they want to enjoy life quickly,” said Sum Costa.
Of his four children, only one followed his steps and at age 20 was "almost ready to become a stlijon" but he died in a car accident, said Costa. Banned by colonial governments, condemned as witchcraft by the church, despised by post-colonial Marxist regimes, African traditional medicine is regaining prestige.
The World Health Organization describes it as “heritage, knowledge and healing that is affordable, accessible, and culturally acceptable” and has declared Aug. 31 International Day of African Traditional Medicine.
Tall, thin and dreadlocked, Kwame Sousa is a local artist and filmmaker, working on a documentary on myths and beliefs of Sao Tome and Principe.
Whenever he sprains an ankle playing soccer, he visits his old stlijon.
“He rubs with a warm, foul-smelling, vinegary potion and in no time I am cured,” he said. “It would be sad to lose this knowledge.
http://www.globalpost.com/dispatch/africa/090830/sao-tome-and-principes-forest-pharmacy