Medicine

Antibiotics
Antibiotics are strong medicines that can stop some infections and save lives. But antibiotics can cause more harm than good when they aren't used the right way. You can protect yourself and your family by knowing when you should use antibiotics and when you shouldn't.

Antibiotics only work against infections caused by bacteria. They don't work against any infections caused by viruses. Viruses cause colds and most coughs and sore throats.

Usually antibiotics kill bacteria or stop them from growing. However, some bacteria have become resistant to specific antibiotics so the antibiotics don't work against them. Resistant bacteria develop faster when antibiotics are used too often or are not used correctly.

Resistant bacteria sometimes can be treated with antibiotics to which the bacteria have not yet become resistant. These medicines may have to be given intravenously (through a vein) in a hospital. A few kinds of resistant bacteria are untreatable.

Antivirals
Drugs used to treat infections caused by viruses. An Antiviral drug is any drug that destroys viruses.

Antiacids
An agent that counteracts or neutralizes acidity (especially in the stomach).

Anticoagulants
Medicine that prevents or retards the clotting of blood.

Antidepressants
Antidepressant drugs are medicines that relieve symptoms of depressive disorders.

Antidepressant agents act by increasing the levels of excitatory neurostransmitters. The main types of antidepressant drugs in use today are:

• Tricyclic antidepressants
• Selective serotonin reuptake inhibitors (SSRIs or serotonin boosters)
• Monoamine oxidase inhibitors (MAO inhibitors),
• Tetracyclic compounds and atypical antidepressants which do not fall into any of the above categories

All antidepressant agents, regardless of their structure, have a slow onset of action, typically three to five weeks. Although adverse effects may be seen as early as the first dose, significant therapeutic improvement is always delayed. Similarly, the effects of antidepressants will continue for a similar length of time after the drugs have been discontinued.

Antihypertensives
Drugs that reduce high blood pressure

Blood pressure is a measure of the force of the blood pushing against the walls of the arteries. Hypertension refers to an elevation of the blood force against the arterial walls. It is an indication that both the heart and the blood vessels are being overworked. Antihypertensives lower blood pressure by 1) opening and widening the blood vessels, 2) preventing the blood vessels from closing and tightening, or 3) reducing the workload of the heart. These medications include the following:

Alpha blockers
Medications that reduce the workload of the heart by blocking certain chemicals from binding with alpha receptors in the heart. Binding could trigger a rapid heartbeat.

Beta blockers
Medications that reduce the workload of the heart by blocking certain chemicals from binding with beta receptors in the heart. Binding could trigger a rapid heartbeat.

Vasodilators
Medications that expand or widen blood vessels, reducing blood pressure against the walls of the vessels. This allows blood to flow more freely and the heart to pump more efficiently. Vasodilators include the following:

ACE inhibitors (angiotensin-converting enzyme inhibitors)
Vasodilators that block the production of a substance (angiotensin II) that causes blood vessels to tighten. Preventing this constriction allows more blood to flow into the heart and lowers blood pressure.

Angiotensin II receptor blockers (ARBs)
Vasodilators that produce the same effect as ACE inhibitors but by a different mechanism. Instead of preventing the production of angiotensin II, they inhibit the action of this substance by blocking it from entering angiotensin II receptors in the body.

Calcium channel blockers
Vasodilators that reduce the workload of the heart by blocking calcium ions from signaling the blood vessels to constrict or tighten.

Central adrenergic inhibitors.
Vasodilators that act directly on the brain to prevent it from signaling the central nervous system to increase heart rate or narrow blood vessels.

Drugs to treat high cholesterol
There are several different types of drugs to treat high cholesterol. Statins are by far the most popular type of cholesterol lowering drug. Other types include bile acid resins, nicotinic acid (niacin), and fibrates

Statins prevent the body from making cholesterol. Statins are considered to be the first treatment for people with high cholesterol if making lifestyle changes doesn't cause cholesterol levels to decrease. Statins have been shown to reduce cholesterol levels 25 to 40 percent.

Diuretics
Sometimes called "water pills," these medications promote the formation of urine in the kidneys, causing the body to flush out fluids and minerals including sodium. The reduction in fluid volume and sodium levels causes blood vessels to open wider, increasing blood flow and reducing the pressure of blood against the vessels. Of the four types of diuretics, the three used in the treatment of hypertension are loop, potassium sparing and thiazide.

Non-Steroidal Anti-Inflammatory Drugs
Non Steroidal Anti-Inflammatory Drugs (NSAIDs) are medications which, as well as having pain-relieving (analgesic) effects, have the effect of reducing inflammation when used over a period of time.

NSAIDs can be used as simple pain killers (analgesics), but paracetamol is usually preferable, as it is likely to have less unwanted effects, and costs less. They are most useful in conditions which cause inflammation. The anti-inflammatory effects may take from a few days to three weeks to come on, so it is worth persevering for a while before deciding that a NSAID is not going to help.
NSAIDs are used as follows:

• The commonest use of these drugs is for arthritis. Paracetamol is often adequate for osteoarthritis, but NSAIDs are particularly useful in the inflammatory forms of arthritis (eg rheumatoid arthritis) and, sometimes, in the more severe forms of osteoarthritis.
• Back pain and sciatica. Ibuprofen has been clearly demonstrated to be helpful, and the other NSAIDs are also helpful.
• Sprains, strains, and rheumatism.
• Dental pain.
• Post-operative pain.
• Period pain (dysmenorrhoea) and heavy periods (menorrhagia).
• Pain from kidney stones (renal colic).
• To help reduce temperature in someone with a fever.
• Migraine.
• Other painful conditions, especially where there is inflammation.

The NSAIDs work by affecting some chemicals in the body which cause inflammation, the prostaglandins. Unfortunately the same group of chemicals are involved in the stomach, and so the NSAIDs tend to cause indigestion, and may even cause duodenal or stomach ulceration.
As a result of this side-effect they cannot be used in someone with a history of peptic ulcer, except in exceptional circumstances, under close medical supervision. Also they would rarely be used and, if used, only with extra care, in somebody with heartburn or indigestion.

Anxyolytic Drugs
Tranquillizer or minor tranquillizer are commonly used terms for a number of drug types which include:

• Sedatives. These slow down the brain and the body. They are often prescribed for use when people are upset or anxious.
• Hypnotics. These are used to induce sleep - they are usually called sleeping pills. Hypnotics work by slowing the brain down.
• Anxiolytics. These aim to take anxiety away.