Substance use disorder (SUD) is a chronic disorder that influences the brain, behavior, and general wellness of a person. Most individuals are unaware of the initial symptoms until the condition deteriorates, which is why it is important to get to know what SUD is like. Whether it is you or a loved one, it is better to know the symptoms and signs so that you can take the necessary action early enough and seek the necessary support. What is Substance Use Disorder? Substance us