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HOW DOES SAW PALMETTO WORK: INHIBITING THE CONVERSION OF TESTOSTERONE TO DHT
As previously discussed, one of the causes of BPH is the influence of DHT on prostate cells. If the levels of DHT can be decreased within prostate tissue, there is a good chance the gland will shrink enough to allow urine to flow out easier. Can SP block the conversion of testosterone to DHT?
It depends on which laboratory is doing the study. In 1993, scientists at Merck Research Laboratory in Rahway, New Jersey, after evaluating Proscar and SP on rat prostate tissue, concluded that SP does not have the ability to block the conversion of testosterone to DHT while finasteride (Proscar) does. A year later, a research group from Hopital Universitaire Cochin, in Paris, determined that the administration of SP extract for a one-week period to 32 healthy male volunteers did not reduce DHT levels in blood; but Proscar administration at 5 mg a day did reduce blood DHT levels. Merck which sells Proscar, funded this study as well.
The findings by Merck researchers conflict with earlier studies financed by the company promoting Permixon which found that SP did have the ability to block the conversion of testosterone to DHT.
Many individuals now have easy access to Medline and other medical data information systems through their computer. For instance, if someone wanted to find out more about SP, they would type in saw palmetto or Serenoa repens and abstracts of studies on this herbal extract would show on the screen. What doesn't appear within the abstract, but is mentioned in the full article published in a journal, is who is funding the study. What's disturbing is that doctors, the media, or anyone who wants to learn more about SP, or any other supplement, won't realize that some of the information they are reading may not be completely accurate. The results of a particular study may be influenced by the source of the funding.
Dr. Franco Di Silverio and colleagues, from the University of La Sapienza in Rome, Italy, wanted to find out the effect of finasteride (Proscar) and SP on the concentrations of DHT in prostate tissue. Six patients were given SP extract (Permixon) at 320 mg/ day for 3 months, 9 patients were given finasteride, and 9 patients were not given any medicines. Prostate tissue was removed surgically from these patients at the conclusion of the three months and levels of DHT were evaluated. In the untreated group, DHT levels were 1121 mg/pg DNA (pg means picogram, one trillionth of a gram). Patients on finasteride showed a level of 232, while those on SP had levels of 256. This study indicates that both finasteride and SP extracts have the ability to decrease DHT levels in prostate tissue. More studies are needed to confirm these findings.
Interestingly, SP does not seem to influence levels of testosterone in the blood. When twenty men, aged 50 to 75 years, suffering from BPH were given 160 mg of SP extract twice a day for one month, there were no changes in their blood levels of testosterone, follicle-stimulating hormone, and luteinizing hormone.
To make things more conflicting, an additional study was published by researchers at the Endocrine Unit of Szent-Gyorgyi Albert Medical University, in Szeged, Hungary. An SP extract, called Strogen forte was found to inhibit prostatic 5-alpha-reductase in rats and humans.
I have read quite a number of articles on SP in the last few years in lay magazines. Almost every one of the authors reports that the mechanism of action of SP is due to its blocking the conversion of testosterone to DHT. Based on the review of all the studies published thus far, I cannot come to a definite determination on whether compounds within SP block the conversion of testosterone to DHT. It would be premature to make this claim. The results of independently funded studies are needed.
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Men's Health Erectile Dysfunction
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Pharmacy Information
BIRTH CONTROL: CONTRACEPTIVES AVAILABLE ONLY WITH A DOCTOR'S PRESCRIPTION
1. A diaphragm is a thin rubber dome-shaped cup stretched over a collapsible metal ring, designed to cover the mouth of the womb (the cervix). Properly fitted and used with a contraceptive cream or jelly, the diaphragm seals off the cervix and prevents sperm from entering the womb. The cream or jelly is toxic to sperm, and provides lubrication as well. This device in no manner interferes with the conduct or pleasure of intercourse.
The diaphragm can be obtained only by prescription from a physician, and must be fitted by him the first time. Because of individual differences in women, a diaphragm of the correct size and shape is of vital importance, both for the wearer's comfort and for its effectiveness as a contraceptive. After the initial examination and insertion of the diaphragm, the physician will instruct his patient how to insert it properly herself, and how to remove it. A virgin cannot be fitted with a diaphragm until the hymen is broken. Physicians are therefore reluctant to prescribe a diaphragm for any woman until after her honeymoon.
A diaphragm may be inserted several hours before or immediately preceding coitus. It must not be removed until four to six hours after intercourse, and it may be left in place for as long as twenty-four hours. Douching (discussed more fully hereafter) is unnecessary, since the natural processes of a healthy woman keep her vaginal tract clean. If she prefers to douche, however, she must wait at least six hours following coitus in order for the spermicide cream or jelly, or the naturally acid condition of the vagina, to destroy the sperm. Diaphragms are considered by many to be inconvenient, uncomfortable, and rather difficult to use. For other couples, the advance preparation implies a loss of spontaneity that detracts from sexual pleasure.
With the use of this device and a contraceptive jelly, the pregnancy rate varies from 4 to 10.
A cervical cap is a small deep cup usually made of plastic that fits snugly just over the cervix. Because the cervix lies so deep within the vagina, and because it is essential that the cap fit snugly, it must be fitted by a physician. Women can be trained to insert the cap, but many seem unable to learn the technique. This method of contraception is, therefore, not often used in the United States, although it is in fairly common use in Europe. Once the cap is fitted properly, the penis is not likely to dislodge it. It cannot be felt by the wearer, and it can be worn the entire time between menstrual periods. Caps made of rubber can be worn only about twenty-four hours. The cervical cap used with contraceptive cream or jelly is considered to have about the same pregnancy rate as the diaphragm used with contraceptive cream or jelly. Because the cervical cap is left in place between menstrual periods, some of the disadvantages of the diaphragm are eliminated.
Oral contraceptives (birth control pills, popularly called "the pill"). It was demonstrated in 1937 that the administration of the ovarian hormone progesterone would inhibit ovulation in rabbits. Since that time endocrinologists, biologists, chemists, and physicians using this and other information, and working together and separately, have developed a method of contraception for human beings that is apparently superior to any method previously employed.1 In 1954, an oral contraceptive in the form of a pill was used in laboratory studies, then two years later in Puerto Rico and Haiti in well-controlled studies to determine its safety and effectiveness. The experiments were tremendously successful. Since that time, pharmaceutical houses have been working overtime to supply the public with the pills, and to produce even better oral contraceptives.
The birth control pill is a combination of synthetic hormones (progesterone and estrogen) that, when taken in adequate doses, prevents ovulation by mimicking the body's natural hormones produced during pregnancy. If no ovum is released, pregnancy obviously cannot occur. The pill actually does several things to prevent or to make pregnancy extremely unlikely to occur. First, pituitary gonadotropin production is inhibited, which interferes with the growth and development of the ovarian follicles. In addition, the uterine mucosa is affected in such a manner as to make implantation more difficult and early spontaneous abortion more likely if an egg were to be fertilized. The mucous plug of the cervix is thickened and made more formidable by the hormonal agents, thereby helping to prevent sperm from entering the uterus.
Counting from the first day of her monthly menstrual period, a woman starts taking the pills on the fifth day. She must swallow one pill daily, and preferably at the same hour, for twenty days. Menstruation will start two to five days after the last pill is taken, although in about 3% of the cases, it fails altogether to commence. In this latter event, a physician usually advises his patient to commence a new round of twenty pills seven days after the last pill was taken, or he will offer alternative suggestions.
If one pill is missed, there is a chance of pregnancy, but it is rather remote. If taken as prescribed, however, contraceptive pills are virtually 100% effectiveand their success is unequalled by any other means of contraception.
During the early months of taking contraceptive pills, women seem to experience little reduction in sexual desire. The knowledge of being well protected against an unwanted conception often removes anxiety from both husband and wife, thereby increasing sexual desire in both partners. Authorities have warned women, however, to expect some loss of sex drive after protracted use of the pills because of their interference with normal hormonal production.3'5 Masters and Johnson report that a reduction in women's sex drive occurs after their taking the pills for eighteen to thirty-six months, and they suggest that other contraceptive methods be substituted for the pill from time to time, according to the advice of the individual woman's physician, in order that the original hormonal balance can be restored.217 The pill is also used to treat certain discomforts and disorders of the menstrual cycle, such as irregularity, too copious flow of blood, and discomfort before or during menstruation.
As contraceptive pills have been used, studied, modified, and improved upon since their initial introduction, the negative side effects have largely been removed. Occasional discomfort or unpleasantness may still be experienced by some women who take them, especially in the first months. The most common symptoms reported are mild gastrointestinal disturbance, nausea and a bloated feeling, increase in weight, and spotting and irregular bleeding. Other occasional negative side effects are persistent menstrual-like cramping and painful swelling of the breasts.
A considerable amount of research is being done on a pill for men that will induce temporary sterility. To date, however, there are unfortunate side effects when men use a pill of this nature, in that sex drive is reduced and the intake of alcohol produces abnormal reactions. Much further experimentation, therefore, in this aspect of contraception is indicated.
This means of contraception, as has been pointed out, is considered 100% successful when used as directed. Even when a woman occasionally misses taking one, the pill still has the excellent pregnancy rate of 3 to 7, equaling the best mechanical device. A birth control pill designed to prevent implantation of the fertilized egg is presently being studied. This pill, if taken just after sexual intercourse, would act for the next few days to prevent implantation of the fertilized egg. Vaccines to immunize people against fertility for several months are also being investigated.
A pharmaceutical house has recently produced an effective oral contraceptive for dogs. The pill, administered each day for thirty days before the female's estrus period, suppresses that period without affecting the animal's capacity for producing healthy litters in the future.318
4. Intrauterine contraceptive devices (IUCDs) are small plastic or metal devicesplastic being preferred over metal because of its flexibility and the greater chance of its not being rejected by the subject's body tissueof various sizes and shapes. They are designed to fit into the womb, and in some way they act as an irritant to prevent implantation of the fertilized ovum in the uterine wall. Technically, this method is more correctly called contraimplantation than contraception.
The device must be selected and fitted in the uterus by a physician. It remains permanently in place until the user wishes to become pregnant, at which time the doctor will remove it. After the birth of a child, it may be repositioned in the uterus until another pregnancy is desired. The device in no way affects the health of any children borne by the woman or her ability to conceive.
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Men's Health Erectile Dysfunction
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