Question: Barry Ricardo Forde (born September 17, 1976) is a Barbadian track cyclist, he was banned for two years and two months after testing positive for Testosterone on October 28, 2005, Testosterone is a medication and naturally occurring what?

Context paragraphs:
Prasterone: Prasterone, also known as dehydroepiandrosterone (DHEA), is a naturally occurring steroid which is used as a supplement and medication.  It is an androstane derivative and a precursor of steroid hormones like testosterone and estradiol.  Prasterone has weak androgenic activity, weak estrogenic activity, and neurosteroid activity, and acts as a prohormone of androgens and estrogens depending on its dosage and route of administration.  As a medication, prasterone may be used to restore or increase DHEA levels in deficiency or old age, for menopausal women as a weak androgen or to treat vaginal atrophy, and, in its sulfate form, for cervical dilation during childbirth.

3α,5β-Androstanediol: 3α,5β-Androstanediol, also known as etiocholanediol, as well as 5β-androstane-3α,17β-diol or etiocholane-3α,17β-diol, is an endogenous, naturally occurring steroid that is formed as a metabolite of testosterone.  It is formed from 5β-dihydrotestosterone (after 5β-reduction of testosterone) and is converted into etiocholanolone.

Ian Browne (cyclist): Ian Browne, also known as "Joey" Browne (born 22 June 1931) is a former Australian track cyclist who along with Tony Marchant won the 2000 m tandem event at the 1956 Summer Olympics in Melbourne.  Unusually tall and strongly built for a cyclist, Browne had little formal training and won his first Australian title in 1953 in the 10 mile event.  Browne did not team up with Marchant until early in 1956 and they promptly won the tandem event at the national championships to earn national selection.  The pair were eliminated after losing their first two races but were given a reprieve when the Soviet Union pair were hospitalised in a crash and forced to withdraw.  Thereafter Marchant and Browne were unbeaten and progressed to an unlikely Olympic gold.  Browne's combination with Marchant was broken after the Olympics when the latter retired.  In 1958, Browne won the 10 mile event at the national titles and went on to win the event at the 1958 British Empire and Commonwealth Games.  Browne went on to compete in the 1960 and 1964 Olympics in the tandem event, both times with new partners, but both times he was eliminated in the repechage round.  In 1964, he became the oldest ever track cyclist to represent Australia at the Olympics at the age of 33.  He won the last of his national titles at the age of 37 in 1968 in the tandem event but was overlooked for Olympic selection by Australian officials.  He retired and later was involved in cycling administration.

3β,5β-Androstanediol: 3β,5β-Androstanediol, also known as epietiocholanediol, as well as 5β-androstane-3β,17β-diol or etiocholane-3β,17β-diol, is an endogenous, naturally occurring steroid that is formed as a metabolite of testosterone.  It is formed from 5β-dihydrotestosterone (after 5β-reduction of testosterone) and is converted into epietiocholanolone.

Barry Forde: Barry Ricardo Forde (born September 17, 1976) is a Barbadian track cyclist.  Forde was banned for two years and two months after testing positive for Testosterone on October 28, 2005.

Patxi Vila: Francisco Javier "Patxi" Vila Errandonea (born 11 October 1975 in Hondarribia, Basque Country) is a Spanish Basque former professional road bicycle racer who rides for the UCI Professional Continental team Szuper Beton .  He was formerly with UCI ProTeam , before being banned for 18 months after testing positive for the use of testosterone.

Zeuterin: Zeuterin ("zū-tur-in") is the trade name of an injectable product containing zinc gluconate and the amino acid arginine, which is used for sterilizing young male dogs without the removal of the testicles.  The product is injected directly into the testicle, where the zinc gluconate destroys the sperm and causes inflammation, which leads to fibrosis and causes sterility.  Sperm production continues for up to 60 days after product administration, and in some dogs does not stop completely, although the product is 99.6% effective when given to dogs aged three to ten months of age.  Following administration, the testicles atrophy; the degree of atrophy may vary noticeably between testicles.  The male hormone, testosterone, is produced in limited quantities following treatment with Zeuterin, but after two years, testosterone production is similar to that in untreated dogs.  The continuing presence of testosterone means that, unlike surgical castration, chemical castration does not remove the risk of testosterone-associated disease, such as prostatic disease.

Gene Samuel: Gene "Geronimo" Samuel (born 15 October 1960) is a semi-retired track cyclist and road cyclist from Trinidad and Tobago, who represented his native country at four consecutive Summer Olympics, starting in 1984 where he placed fourth, missing the bronze medal by 4/100ths of a second.  He won a gold, a silver and a bronze medal in the Men's 1.000m Time Trial at three different Pan American Games.  Samuel is a well known bunch race track cyclist for his never-say-die competitive attitude and his warrior spirit, hence his nickname, "Geronimo".  He broke the World Professional record in the 1000 metre time-trial in Cali, Colombia, in 1992.  He was a World Champion bronze medallist in the 1000metre time-trial in 1991 at the World Championships in Stuttgart, Germany, a few days after winning the Gold medal at the Pan American Games and breaking the track record in Havana, Cuba.  He won double Gold Medals at the 1986 CAC Games in Santo Domingo and broke the 1000m track record in the process.  He has three times been Sportsman of the Year in Trinidad and Tobago and also was inducted into the Sports Hall of Fame in 2000.

Boldenone undecylenate: Boldenone undecylenate (USAN) (brand names Boldane, Equipoise, Parenabol, Vebonol, others), or boldenone undecenoate (BANM), also known as Δ-testosterone 17β-undec-10-enoate, 1-dehydrotestosterone 17β-undec-10-enoate, or androsta-1,4-dien-17β-ol-3-one 17β-undec-10-enoate, is a synthetic, injected anabolic-androgenic steroid (AAS) and androgen ester that is used in veterinary medicine, specifically in horses.  It is a long-acting ester of boldenone, which itself is a naturally occurring androgen (found in the scent gland of "Ilybius fenestratus") and dehydrogenated analogue of testosterone.

Testosterone (medication): Testosterone is a medication and naturally occurring steroid hormone.  It is used to treat male hypogonadism and certain types of breast cancer.  It may also be used to increase athletic ability in the form of doping.  It is unclear if the use of testosterone for low levels due to aging is beneficial or harmful.  Testosterone can be used as a gel or patch that is applied to the skin, injection into a muscle, tablet that is placed in the cheek, or tablet that is taken by mouth.

Supporting paragraphs: Barry Forde Testosterone (medication)
Answer: steroid hormone