The use of prescription patches worn on the skin to deliver medicine directly into the bloodstream dates back to 1980 when a patch to control travel sickness was developed. The obvious advantages of this was that the drug did not need to be taken by mouth and the vomiting associated with motion sickness was therefore no longer an obstacle to its efficacy.

Innovation
This innovation was closely followed by the introduction of the Transderm-Nitro patch, used to treat heart disease. But the idea of impregnating patches with products did not really take off completely until 1996 when the American Food and Drug Administration approved a patch to help smokers quit the habit to be sold over the counter in chemists and skin patches became a more familiar sight.

Nicotine
These nicotine patches help prevent cravings from occurring, but using nicotine replacement therapy does carry the risk of maintaining your physical dependence on nicotine. To avoid this, the dose of nicotine replacement you use must be gradually reduced over a period of 10-12 weeks. Some types of nicotine patch can be worn for 24 hours. The amount of nicotine absorbed through the skin provides lower blood levels of nicotine than smoking, but is enough to prevent cravings and withdrawal symptoms after stopping smoking.

Wide range
Today there are patches for a variety of medical problems including contraception, pain relief, hormone replacement therapy and overactive bladder syndrome. Depression patches are in development, as are patches to treat depression and attention deficit disorder as well as those to deliver insulin to sufferers of diabetes.

Capillaries
The transdermal patches work by allowing substances easy access to the bloodstream through the thousands of capillaries close to the surface of the skin. Drugs can be more efficacious and can help avoid a host of other problems – for example people with gastrointestinal problems who can not consistently absorb drugs consistently are helped, as are those who suffer the side effects of bloating and heartburn.

Elimination
Traditional pills and capsules need to pass through the stomach and liver before reaching the target tissues and less medicine may need to be used because of the patch’s proximity to the bloodstream. Forgetful patients are more likely to comply with their dosing schedule as all they have to do is slap on a patch and go.

Possible effects
However, patches are relatively new inventions on the pharmaceutical market and we don’t yet know everything about them. Sometimes they do not compare exactly to the pill versions either in possible side effects or effectiveness. Since the standard form has been around a lot longer, doctors don’t always know precisely how patients will react to a particular patch medication. The adhesive used can sometimes be irritating for patients with sensitive skin. Although they are waterproof they may slide off while bathing, sweating or become less effective when wet or dirty.
Convenience
There is also the problem of over-convenience – what if you forget to take it off and switch it for a fresh one? However, when compared with the contraception pill, the user has to remember a lot less frequently. “Ortho evra”, for example, is a hormonal patch which is stuck to the skin once a week to prevent pregnancy. The patch stays on for a week and is then changed on the same day for another one for three weeks, with a one week resting period. The patch can be applied to the buttocks, abdomen, front or back of the torso or the outside top part of the arm.
Another advantage of patches is that drugs that are potential candidates for abuse can be prescribed in such a way that the risk is eliminated. For example Fentanyl (in Spanish fentalino) is a powerful opiate analgesic sold in transdermic patches under the brand name Durogesic®. It is indicated for the treatment of severe oncological pain and uncontrolled pain requiring treatment with opioids.

Slow release
Long-acting pills are the alternative. The downside is if the patient suffers side effects they may have a long wait before they go away, but for some patients, long acting pills have real advantages over shorter acting ones. For example Fosamax, a drug taken for osteoporosis has to be taken on an empty stomach with a glass of water while standing up for 30 minutes. The less frequently a procedure such as this has to be followed, the better.

Controlled drugs
Controlled drugs with high rates of addiction and abuse can sometimes be given for medicinal purposes using patches, as devices preventing abuse can be manufactured into the fabric.
Opiate drugs such as morphine are often administered in this way, and medical research is being conducted into harnassing the pain-killing power of cannabis into patches, so deliver doses in a controlled manner.

Alternatives
Alternative medicine is also available in patch form, for example tiger balm patches are available for muscle pain and injury. Their warm penetrating action is said to provides rapid, temporary pain relief and comfort for hours. There are also anti-itch patches, Echinacea (said to boost the immune system) patches, ginkgo biloba, glucosamine and green tea patches (said to promote rapid weight loss).

Appearance
Patches are being made to blend in with different skin tones to make them less noticeable. After all, if you are of African origin, a white patch is going to be ver obvious, and pharmaceutical companies are taking this into account.

Always consult your doctor before using patches, even if sold over the counter.