If you find yourself questioning the mental health of your child, you may want to ask yourself if you should be worried. You need to seek the advise of a doctor and then talk to your child to find out what is going on. If it's a false alarm, you child will know that they are loved and you are only looking out for them, but you could end up saving your child because of being nosey.
The first thing that a parent must do is distinguished between sadness or typical teenage moods and depression. If you notice a pattern with their moodiness then it is most likely a hormonal thing, but if you seem to notice that, their mood is not changing and it's been weeks, you may want to think about seeking medical advice. Don't take your child with you the first time you go to a therapist for advice. If there isn't a problem then the child could react negatively and won't trust you.
If you suspect that they are depressed all you can do is let them know that you are there for them and that you love them and will support them through anything. You don't need to ask any questions, but just state that you're worried or concerned. You should not judge anything that they do. If they are depressed, it could just be one little innocent comment that pushes them over the edge. You should also encourage them to be more sociable if you notice that they are pulling away from friends and family. You may not only want to seek a therapist to consult, but locate a support group so that you will be able to able to judge the situation without the rose-colored glasses.
Some ways to treat teenage depression family therapy, group therapy, behavioral therapy, exercise, creative expression, volunteer work, medication, hospitalization, boot camp. Therapy is the best way to go, because at that time in a person's life they need someone to talk to that isn't biased. They need that third person.
Exercise is for mild cases. By giving them encouragement to seek out new things, it could help their feelings of restlessness. Encourage your child to use a positive outlet known as art. Have them write, paint, act out the feelings that are inside. People helping people makes others feel good and it could help your child's depression too. Medication, hospitalization, and special schools of boot camps are the last resorts.
Try medication, if that doesn't work then they may need to leave their environment. If you feel that your child is self-destructive, they need to watched and admitted. The special schools are recommended because they get the child out of their environment and develop confidence and learn coping skills.