You’ve probably seen the commercials on television talking about the “you” you used to be before depression set in. Such commercials are generally aired by drug companies promoting an anti-depressant. But what these commercials fail to tell you is depression is common, and not everyone who feels down or blue is suffering from depression. You need to know the facts about depression before you and your doctor determine you are indeed suffering from this illness.

That’s right. Depression is a real mental illness that often requires anti-depressants or therapy to relieve symptoms. You can’t fix depression by yourself, and without treatment, you’ll likely face an uphill battle you probably aren’t going to win. More than 18 million people a year—or nine and a half percent of adults in America—are diagnosed with some sort of depressive illness such as depression.

The first thing you need to know are some of the symptoms that are common with depression. Symptoms include: feeling persistently sad or anxious, being overcome by hopelessness or pessimism, loss of interest in things you normally enjoy, having a lack of energy, feeling excessively tired, having difficulty making decisions or concentrating, insomnia, sleeping too much, excessive weight gain, excessive weight loss, irritability, restlessness and thoughts of suicide. If you’ve experienced any, most or all of these symptoms for a period of two weeks or more, you’re likely to be suffering from clinical depression.

What causes depression? In some instances, depression is genetic and is passed from generation to generation while others who suffer from depression will find there is no history of depression in their families. If you tend to have low-self esteem or you generally are pessimistic, you may be prone to depression. Many changes—such as death in the family, illness, financial difficulties and other stressors—can also be the root cause of depression.

Whatever the reason, it’s important to see a doctor to discuss treatment options. Once your doctor diagnoses depression and eliminates any other possible causes, you and he will determine the best treatment option for you. Antidepressants are often the most chosen form of therapy, and it’s important to know—no matter what antidepressant you go on, you must be sure you never just stop taking them. Simply stopping medication can have severe consequences.

If you take an anti-depressant, you may experience any of a series of side effects including dry mouth, constipation, bladder problems, dizziness, sexual problems, headache, nausea, nervousness and insomnia. If the side effects are too severe, seek your doctor’s advice.

The good news is, if you’re suffering from depression, you’re not alone. You can get help. There are people who understand and who can help you and your family learn to make things better. The key is to seek help, and before you know it you’ll be on the path to happier times.