Ketamine, an anesthetic used in both human and veterinary medicine, have been demonstrated to relieve major depression in research subjects in less than an hour. The effects of a single small intravenous dose were also long-lasting, with improved mood lasting an average three days, some benefits remaining for about a week, and full depression not returning for about two weeks.

Ketamine's rapid antidepressant response has been studied in two disorders – major depression and bi-polar disorder. In the most recent study, published in 2010, researchers at Maryland's National Institute of Mental Health (NIMH) administered low doses of ketamine to 18 patients with treatment-resistant bi-polar disorder. More than half of the patients experienced a reduction in their symptoms within 40 minutes, with 13 percent reporting a near 100 percent improvement. Side effects were mild and brief, and included feeling "strange", a dry mouth, and a rise in blood pressure and heart rate.

A small study of depression sufferers out of Yale University ten years earlier also produced dramatic results. All seven subjects, who had failed to respond to conventional treatments including antidepressant medications, responded well to ketamine, with some of them reporting a profound improvement. Medical reports from the 1950s and 60s noted that tuberculosis patients treated with ketamine experienced rapid relief of their depression symptoms.

Ketamine has been around for 50 years, most recently as the trendy but illegal club drug "Special K", popular for inducing a dreamlike state. Ketamine affects the brain's glutamatergic system, which plays a role in memory and information processing. Ketamine is known to block a class of brain receptors called NMDA receptors from receiving the brain chemical glutamate. NMDA receptors move nerve signals between neurons. Research indicates that the signaling of gluatamate between neurons in this system plays a role in depression. Ketamine also improves the response of another receptor that helps regulate the electrical flow of brain cells.

Ketamine is creating a stir in the medical community, creating hope that the study results will lead to the development of a new class of faster and longer-acting antidepression medication. "These new findings demonstrate the importance of developing new classes of antidepressants that are not simply variations of existing medications," says Dr Elias A. Zerhouni, Director of the National Institute of Health. Research on rapid antidepressant drugs is now "an area of focus within the industry", according to Lee Schechter, the director of preclinical depression and anxiety research at Wyeth Pharmaceuticals.

Major depressive disorder is the leading cause of disability for Americans aged 15 to 44, and is nearly twice as common in women as in men. Bi-polar disorder usually appears in early adulthood, affecting about 5.7 million Americans. Traditional treatments for depression include therapy, electroconvulsive therapy and antidepressant medication. Bi-polar disorder is usually treated with therapy and lithium carbonate or anti-convulsant medication.

Currently, the most commonly prescribed antidepressant medications are selective serotonin reuptake inhibitors (SSRIs) such as Prozac and Zoloft, serotonin-norepinephrine reuptake inhibitors (SNRIs) such as Effexor and Cymbalta, and the norepinephrine-dopamine reuptake inhibitor (NDRI) Wellbutrin. While they help about 80 percent of depression sufferers, antidepressant drugs may take two to six weeks to become effective, and are not without side effects. Common antidepressant side effects are upset stomach, weight gain, fatigue, dizziness, insomnia and sexual dysfunction. Side effects tend to be fewer with Wellbutrin, and don't include weight gain or sexual problems. Wellbutrin is sold as Wellbutrin sustained release (SR) and Wellbutrin extended release (XL), and is also prescribed for seasonal effective disorder and as an aid to quit smoking. It is frequently prescribed along with an SSRI for added effect. Affordable generic Wellbutrin is also available.

A 2006 study by the National Institutes of Health found that only 30 percent of depression patients responded fully to their first prescribed antidepressant. Those that responded quickly were more likely to have been taking a higher dose of antidepressant medication, and taking it for longer. Some antidepressant medications are more effective than others depending on the individual, and it's not uncommon for patients to try several antidepressant drugs before they find the best one for them. Some people do best on a combination of antidepressants.

Your doctor or psychiatrist will work closely with you to determine which antidepressant drug or drugs to prescribe, taking your symptoms and situation into consideration. For example, if you are having trouble sleeping or your depression is accompanied by nervousness, you may be prescribed an antidepressant that has a calming effect. If you are overly tired or withdrawn you may be prescribed an antidepressant medication with a stimulating effect. One antidepressant, Celexa (also available as generic citalopram), seems to work better for women than for men. Your doctor will also consider any other medical conditions you may have, and any other prescription and over-the-counter medications you are taking.

Most antidepressant medicines are believed to work by increasing the activity of chemicals in the brain called neurotransmitters, in particular serotonin, dopamine and norepinephrine. Today's most frequently prescribed antidepressants are the selective serotonin reuptake inhibitors or SSRIs (such as Celexa, Prozac and Zoloft), and the newer serotonin and norepinephrine reuptake inhibitors or SNRIs (such as Effexor and Cymbalta). Another new class, norepinephrine-dopamine reuptake inhibitors or NDRIs (Wellbutrin and Zyban), is being increasingly prescribed.

All three have fewer adverse side effects than the older classes of antidepressant medications, such as tricyclics and monoamine oxidase inhibitors (MAOIs). The most frequent antidepressant side effects are upset stomach, dry mouth, sleep disturbances, weight gain, anxiety, and impaired sexual function. Wellbutrin is not associated with weight gain or sexual impairment, and is frequently prescribed along with an SSRI for added effect. Marketed as Wellbutrin sustained release (SR) and Wellbutrin extended release (XL), it is also available as cheaper generic buproprion. Wellbutrin is also prescribed for seasonal effective disorder and as an aid to quit smoking. Talk to your doctor about any unpleasant antidepressant side effects you may experience, as he or she may be able to suggest a way to minimize them. Remember that most side effects ease as you continue treatment.

It's important to stay on your antidepressant medication long enough for it to become effective, without skipping doses. It usually takes at least two weeks until patients begin to feel the benefits of their antidepressants, and it can take up to eight weeks for antidepressant drugs to reach full effectiveness. It's also important not to stop taking your antidepressant medication suddenly. You will likely need to reduce the dose gradually to avoid unpleasant withdrawal symptoms like headaches, nausea and dizziness, and to avoid a possible increase in your depression. Most people who take antidepressant medication need to stay on it for six to nine months. Some patients will need to take an antidepressant indefinitely.

Antidepressant medication has been associated with suicidal thoughts in youth and young adults during initial treatment, and the FDA has issued a safety warning regarding their use in this population. Americans' use of depression medications doubled over the decade between 1996 to 2005, and is continuing to rise. Antidepressants have greatly improved the quality of life for many adults. Statistics show that suicide rates, which had held steady for 15 years, dropped with the introduction of the SSRI Prozac, and continued to drop over the next 14 years as Prozac sales rose, especially among women. The most effective depression treatment is a combination of medication and psychological counseling.

One of the world's most popular painkillers has been linked to an increased risk of asthma in teenagers. Researchers studying almost 323,000 teens from 50 different countries discovered that those that used acetaminophen as little as once a month were at double the risk for asthma. Even those that used the popular painkiller as seldom as once a year had an almost 50 percent greater risk of asthma than teenagers who never took acetaminophen.

Teens that used acetaminophen, best known as Tylenol and one of the oldest and most trusted over-the-counter pain relievers on the market, were also more likely to experience eczema and hay fever-like allergy symptoms such as stuffy noses and watery eyes.

The researchers claim that evidence is accumulating that the extensive use of acetaminophen over the past 30 years may be contributing to rising asthma rates. Earlier research by the same team linked the use of acetaminophen in a child's first year of life with an increased risk of asthma as a toddler and pre-schooler.

While a clear link has been established between acetaminophen and asthma, it's still not known whether the painkiller itself is triggering asthma, or the teenagers are taking acetaminophen in response to something else causing their asthma, such as a viral respiratory infection like the common cold.

Still, the researchers say results strongly suggest acetaminophen may interfere with the immune system, triggering an allergic response. One hypothesis is that acetaminophen lowers the body's levels of glutathione, an antioxidant important in protecting the lungs from damage by free radicals formed by oxygen. All pain relievers work by different mechanisms, and acetaminophen is the only one believed to have an effect on glutathione.

"Randomized controlled trials are now urgently required to investigate this relationship further and to guide the use of antipyretics [drugs that reduce fever], not only in children but in pregnancy and adult life," said lead study author Dr. Richard Beasley, adding that almost half of severe asthma cases might be prevented by avoiding the use of acetaminophen.

The study was conducted by researchers from the Medical Research Institute of New Zealand who are part of the International Study of Asthma and Allergies in Childhood, and published online in the American Journal of Respiratory and Critical Care Medicine.

Asthma is the most common chronic condition in childhood, and affects about nine million American youth. Teens with asthma should be encouraged to educate themselves about their condition, and to manage their own asthma medications. It's crucial that they understand what their asthma medications do and how to use them properly.

Asthma treatment usually involves two classes of asthma medication, quick-relief or rescue medications used to treat asthma attacks, and long-term control asthma medicines used to manage chronic symptoms and limit or prevent attacks. Too many teens rely on rescue asthma inhalers to manage their symptoms, and should be made aware of the importance of preventative asthma medications to avoid lung inflammation. Asthma medications are typically provided in a metered-dose asthma inhaler or as dry powder asthma inhalers. Big Mountain Drugs is currently offering an Advair coupon for extra savings on asthma inhalers.