Are mental illnesses inherited?

Meena,
Mental illnesses are very complex disorders that are usually the result of inherited factors as well as life experiences and stresses. With bipolar disorder, doctors and scientists generally believe that the symptoms (depression, mania, etc.) are the result of chemical imbalances in the brain. While the exact neurological mechanism is not yet know, it may involve imbalances in neurotransmitters like serotonin and dopamine. A person can be genetically predisposed to developing such chemical imbalances. So, your son may have been born with such a predisposition, but the actual changes that cause the bipolar may not have happened until he was older. Stress, traumatic experiences, and possibly changes in hormones can contribute to the development of chemical imbalances as well. It usually takes the combination of genetic predisposition and environmental factors to kick start bipolar. So, while other members of your family may have the genetic predisposition to develop bipolar, they may not have had the experiences needed to trigger development of the disorder. I can tell you with certainty that bipolar can run in families. I am one of at least 5 people (across 3 generations) in my family that has bipolar.

I am Bipolar and have had it for 35 years and have run a website and forum for it for the last 10 years. Bipolar is almost always genetic. You may not know someone has it because they are very good at hiding it. No one knows that I have it and I suffer terribly-- I just bite it back. Actually meds have helped tremendously so I feel much better. Look ?nto your family tree for people who were known for being eccentric, or real bastards, or people who had substance abuse issues. Those can be markers.

Families will deny it exists. My mother's step-sister has been hospitalized for Biploar many times. Their shared parent, my mother's father was a hugely talkative man who would talk and not notice that the people around him were about to fall out of their chairs from exhaustion (pressured speech is a marker). I remember his mother was an incredible grumpy woman who scared me. Even with these clues my mother REFUSES to consider that my Bipolar comes from her side of the family. She points to a great grandfather on my father's side who was an itinerant preacher during the Depression. My mother I think has ADHD. She has never been able to sit still and is hugely non-empathetic.
Bipolar tends not to show up until the teens. I have run a forum for people with Bipolar for ten years and poll after poll has shown teenaged presentation.

You are welcome, by the way, to join our forum (http://www.thecyclothymiacollective.blogspot.com) and ask as many questions as you like, or your son is welcome to come. Please know that you are not alone, and that medications can really make a positive difference.I started meds when I was 38 and it was only after that that I started writing novels, designing web sites, doing photography and riding horses. I have been married 25 years and have had the same job for 20 years. You can live a full life with Bipolar.

I have bipolar disorder that began with depression when I was 19.