The Internet has changed the way we live, work and shop. The growth of the Internet has made it possible to compare prices and buy products without ever leaving home. But when it comes to buying medicine online, it is important to be very careful. Some websites sell medicine that may not be safe to use and could put your health at risk.

Millions of consumers are using the Internet to get health information. And thousands of web sites are offering health information. Some of those sites are reliable and up-to-date; some are not. How can you tell the good from the bad?

Make sure the site requires a prescription and has a pharmacist available for questions.

There are more opportunities today than ever before to learn about your health and to take better care of yourself. It is also more important than ever to know about the medicines you take.

If you take several different medicines, see more than one doctor, or have certain health conditions, you and your doctors need to be aware of all the medicines you take. Doing so will help you to avoid potential problems such as drug interactions.

Reading the label every time you use a nonprescription or prescription drug and taking the time to learn about drug interactions may be critical to your health. You can reduce the risk of potentially harmful drug interactions and side effects with a little bit of knowledge and common sense.

When a drug is taken orally, it usually travels from the stomach to the liver, where it can be metabolized-the process of breaking down and removing chemicals from the body. Enzymes are complex proteins that act as catalysts in starting or speeding up chemical reactions. They cause a specific chemical change in other substances without being changed themselves.

The most important enzymes in the liver that metabolize drugs are called the cytochrome P450 family of enzymes. These enzymes break down drugs when they pass through the liver or small intestine.

A drug may affect these enzymes by inhibiting them, which causes reduced activity of the enzyme and a buildup of the drug in the body. Or drugs may "induce" the enzymes, which causes increased activity of the enzyme and a reduction of the drug in the body.

Over the last several years, there has been a substantial increase in the number of drug-interaction studies the FDA sees in new drug applications. If drug interactions are significant enough, they can prevent a drug from being approved by the FDA. If the agency determines that known drug interactions can be managed and that a drug's benefits outweigh the risks for the intended population, a drug will be approved. Drug-interaction information then goes into the drug's labeling in the sections on "clinical pharmacology," "precautions," "warnings," "contraindications," and "dosage and administration."

Drug interactions with food and beverages, for example, taking quinolone antibiotics such as ciprofloxacin with food and drinks such as colas, coffee, and chocolate that contain caffeine may cause excitability and nervousness. There can be a potentially fatal increase in blood pressure if food containing tyramine is eaten when taking monoamine oxidase inhibitors, drugs that treat mood disorders.

Although medicines can make you feel better and help you get well, it's important to know that all medicines, both prescription and over-the-counter, have risks as well as benefits.

The benefits of medicines are the helpful effects you get when you use them, such as lowering blood pressure, curing infection or relieving pain. The risks of medicines are the chances that something unwanted or unexpected could happen to you when you use them. Risks could be less serious things, such as an upset stomach, or more serious things, such as liver damage.

There are several types of risks from medicine use: a) The possibility of a harmful interaction between the medicine and a food, beverage, dietary supplement (including vitamins and herbals), or another medicine. Combinations of any of these products could increase the chance that there may be interactions. b) The chance that the medicine may not work as expected. c) The possibility that the medicine may cause additional problems.

The benefit and risk decision is sometimes difficult to make. The best choice depends on your particular situation. You must decide what risks you can and will accept in order to get the benefits you want.

For example, if facing a life-threatening illness, you might choose to accept more risk in the hope of getting the benefits of a cure or living a longer life. On the other hand, if you are facing a minor illness, you might decide that you want to take very little risk.

In many situations, the expert advice of your doctor, pharmacist, or other health care professionals can help you make the decision.

Important: think it through and work together with your doctor, pharmacist, or other health care professional to better manage the benefits and risks of your medicines.

You need keep an up-to-date, written list of ALL of the medicines (prescription and over-the-counter) and dietary supplements, including vitamins and herbals, that you use--even those you only use occasionally.

Ask your doctor always if there are interactions with any other medicines or dietary supplements (including vitamins or herbal supplements), beverages, or foods. Use the same pharmacy for all of your medicine needs, whenever possible.

Before starting any new medicine or dietary supplement (including vitamins or herbal supplements), ask your doctor again if there are possible interactions with what you are currently using.

Modern dental clinic help your teeth