“Can bipolar disorder be left untreated?”

Increased risk of drug and alcohol problems, divorce, arrest, premature death left untreated

Bipolar disorder can worsen if left untreated. As a result, episodes can be intensified and more frequent, which can strongly affect a person's overall life.

If your friend has been diagnosed with Bipolar disorder, it cannot be left untreated. It is likely that he either has symptoms (which he may or may not acknowledge)--or will have symptoms in the future. Either way, he should be monitored by a psychiatrist (who can prescribe medication) and also do psychotherapy with a therapist, who will help him with coping strategies for life.

Like many illnesses, psychiatric or medical there is always an option to treat or not to treat and depending on the illness there is a risk option. With some medical problems one risks their life with psychiatric illnesses that is not often true...True Bi=Polar, meaning Bi=Polar Type I can get out of control and the individual can become flagrantly manic., This would refer to psychotic or the person may hallucinate and/or become delusional...they will have a tendency to engage in risky behaviors such as overspending money, getting involved in promiscuous sexual relationships, gambling or excessive use of drugs and alcohol. In the depressed phase there is always the risk of suicide.

So, having said that I have treated patients with talking therapy only and some have done great for a number of years, once even as much as l0 years without an episode leading me to question my original diagnosis...of course as I was beginning to doubt my diagnostic skills she spiraled into an out of control psychotic manic state and ended up involuntarily committed to a hospital...on the other hand there are also some people who cannot go for six or eight weeks without professional treatment lest they begin severely impaired.

Each individual makes their own decision but those that choose not to treat are often doing so while putting their family at considerable risk for humiliation, financial ruin or crumbling family relationships.

There is a great risk if the patient goes into manic episode. 

Appropriate medical treatment plus cognitive behavior therapy is the best combination and can be quite helpful.

Take a peek at this link for some insight into your question:

https://www.mayoclinic.org/diseases-conditions/bipolar-disorder/symptoms-causes/syc-20355955