The drugs actually can be the primary cause. Simply because they are not the proper ones for the ailment. You can take an Average Joe or Jill having trouble sleeping, having mild depression, having mild anxiety, want to stop smoking, and they through an adverse reaction caused by the medications triggering a digestive chemical migration from stomach to the brain and it have the same effect in their brain as LSD. I saw it happen to a person I knew very well and not one doctor in six could diagnose it.
Now granted the onset of what I'm speaking of is usually fairly fast happening most of the time over a period of hours or a few days. Look up Serotonin Syndrome. It involves antidepressants usually ones which can be prescribed to help loose weight, stop smoking, treat anxiety or depression etc.
Many symptoms of what people call mental disorders such as Anxiety and Depression very often aren't and have a neurological or physical ailment causing it and it doesn't get diagnosed but instead gets treated with an improper medication for that ailment.
An example I know first hand is Inner Ear {Vestibular and Sensory Processing Disorders} can trigger symptoms anxiety as a secondary condition. Older doctors the older now retired General Practitioners would give the patient a script for Valium or similar to treat the symptoms and treat the underlying cause {the infection or find reason for the damage}. Used to most people knew an Inner Ear infection would about drive someone nuts.
Worse is the fact due to a lot of misinformation and media hyped fear even within the medical community involving medications like Xanax, Valium, Atavian, etc which are far more feared and restricted than Antidepressants being prescribed without second thought. You will not get a Serotonin migration from Benzo's actually they are the protocol antidote treatment to stop Serotonin Syndrome. A Benzo can be given in a doctors office and the patients reaction seen in minutes. Antidepressants take several weeks to reach therapeutic levels in the bloodstream. In those several weeks the doctor may have a 5 minute observation of the patient.
Safe use of antidepressants require the doctor, patient, and patients family, ALL understanding the symptoms of adverse reactions so they can be stopped fast. Many antidepressants are in the bloodstream for weeks instead of hours. Thus the triggered adverse reaction may go on for a week or more. Something as simple as taking Zoloft and then a few months later catching a cold and taking an OTC cold medication can trigger this also. This isn't Tin Foil junk science it's been proven many times.
I am diagnosed with General Anxiety Disorder. At about 8 they said I had ADD ADHD. I'm 57 now BTW. I've had G.A.D. over 20 years. My sensory auditory and partially my optical processing system is shot. Initially I went on Xanax 2MG twice a day 21 years ago. Then the doctor decided Xanax was too dangerous and started me on antidepressants instead. Then the symptoms got worse as did my mental state in general. That went on for two years. I had headaches, stomach issues, anxiety increased as did sensitivities to triggers to my anxiety such as noises. All were early warnings that the Serotonin in my body was becoming off balanced. I didn't know that then though.
I finally did some research and found out that Anxiety Disorders, Depression, and even the ADD ADHD symptoms I had dealt with since early childhood was caused due to Vestibular Damage. Vestibular is Inner Ear Cerebellar/Vestibular which is where the Inner Ear and portion of the brain responsible for interpretation of the Inner Ear is damaged often due to ear infections allergies etc. Finally a doctor who knew what he was seeing and treating put me on a half a mg of Xanax four times a day. Something the so called experts warn can not work long term. While it's not a cure it allows me to function somewhat like do the shopping etc. I'm a risk to no one LOL. I'm a 20 year user of it and will be a life long user of it. So what I am saying is you can not treat this disorder with protocol antidepressants as it can produce and/or trigger psychotic symptoms mistaken for mental illness.
More to the point I saw my wife develop Serotonin Syndrome from taking Zoloft and Trazodone prescribed by a Shrink. She had PTSD, clinical depression, and anxiety, as well as severe neurological damage resulting in her quadriplegia. Yeah one would expect her to have some depression and anxiety right? Her character changed literally in hours out of the blue several months into using antidepressants. The doctors were so darn certain she was psychotic from severe mental illness that they didn't bother with doing a basic PDR search of her medications for known adverse reactions. They didn't do it but I did. It nearly killed her. I showed the attending doctor {not our primary care doctor who wasn't allowed to treat her or have any say due to hospital privileges rules} the alert article. His prompt response was that's all pure rubbish. He saw the title and didn't read the article. I told him to read the authors name and position to me and then read the article. It was the Pharmacology Professor at the university hospital he worked for. He backed down fast. The MRI told the rest of the story.
Serotonin belongs mainly in the stomach and promotes digestion. When it migrates into the brain it is a very potent chemical that can induce psychotic symptoms the person most likely is unaware of. Why? Because they are hallucinating.
On one end of the spectrum there are antidepressants being passed out without proper education to patients and families because most doctors never see the adverse reaction. On the other end of the spectrum you have patients that by the nature of their very real mental illness do not take their medications.
Your story is interesting and gives much to consider. You seem to suggest that doctors now look for a pharmaceutical remedy for every ailment and that the drug is often worse than the original disease, both of which assertions I agree with. Especially when it comes to children.