The Effects of Mental Illness and Drug Abuse

Which Comes First? Substance Abuse or Mental Illness

There is no clear-cut answer to this question as you can start taking certain types of drugs (legal prescriptions or street illegal drugs) and this will change your thinking processes over time, moving into mental illness with various dependencies. Alternatively, you suffer bouts of depression over years, due to traumatic life events, and you find a drug that makes you feel happier, so you take more of that to feel better for longer periods of time.

If you cannot get that drug, for one reason or another, then your depression returns, worse than before. When a comprehensive medical assessment is made, the outcome is substance use disorder (SUD) and the patient is encouraged to enter one of many San Diego detox centers for rehabilitation and recovery under a dual diagnosis treatment (San Diego) umbrella of resources.

Before any rehabilitation program begins, a treatment outline is designed for the patient, based on the patient’s unique factors which include:

  • age,
  • how long the substance has been used,
  • genetic body chemical markers,
  • numerous health tests (blood, urine, evidence of cancer or other illnesses, etc.),
  • mental assessments, and
  • getting the primary physician and family members involved to assist in the patient’s treatment.

Consequently, each program is different from the next patient’s program even if there are many similarities between the two patients. If a process is not working as desired, the treatment can be adjusted further until the right process is uncovered and implemented.

How Drug Abuse and Mental Illness Affect the Human Body

There are many ways that drug abuse and mental illness can affect a person’s body. Nearly 40-60 percent of vulnerability to SUD is tied to genetics, according to the National Institute of Health (NIH) on Drug Abuse. Interactions between multiple physical genes, combined with current environmental influences (high-stress household, violence, etc.), the body’s retention of drugs over time, response levels to surrounding stress (fight or flight), and more.

Brain cells are also affected, including those of adolescents engaged in the frequent use of marijuana, when their brain cells are still not fully developed yet. Evidence shows that in later adulthood, these young patients exhibit greater instances of psychosis as they mature.

Continuous stress and trauma in life events, including those experienced by our warrior veterans while on the battlefield, can easily lead to substance abuse if not treated in the initial stages. Without treatment, the outcome can lead to post-traumatic stress disorder (PTSD). PTSD is usually defined by the following symptoms:

  • Intrusive memories of traumatic events, such as rape, assault, brutal verbal abuse,
  • Avoidance talking about the traumatic event with others,
  • Frequent nightmares about the event, and
  • Severe emotional and physical reactions, such as a racing pulse, easily startled, instant fear over a sound similar to gunfire or a bomb going off, and more.

If these symptoms increase over time, such events can lead to depression and suicidal thoughts that must be addressed quickly. If you know of someone who needs help because of PTSD, especially combined with substance abuse, call the National Suicide Prevention Lifeline at 1-800-273-8255 to get assistance from a trained counselor.

Changes in Physical Appearance

There are several changes in a person you know well, that could indicate both mental illness issues and substance abuse, such as:


  • Loss of weight or weight gain, due to sitting around or sleeping too much,
  • Red or blood-shot eyes, lack of hygiene (needs a shower desperately), dullness in appearance,
  • Dry mouth and/or bad breath,
  • Sleeps too much or is wired all the time,
  • Exhibits the shakes (hands, other parts of the body),
  • Does not wash clothes or bedsheets and towels, overload of dishes in the sink, especially if this person used to be a clean freak.


  • Takes more drugs than before, including prescriptions of opioids, or other pain drugs,
  • Short of temper, quick to anger bordering on violence, does not want to talk to anyone, refuses to go anywhere,
  • Has extreme changes of personality – from feeling very happy to deep depression in a short span of time,
  • Skips work and/or school more often than usual, gets fired or drops out,
  • Lack of energy and motivation to do anything, such as a clean house, study a program to learn new skills, lack of ability to focus on anything, etc.,
  • Exhibits paranoia and/or anxiety, confusion at times, and even hallucinations.

If you are encountering unusual sudden physical changes and personality issues with a loved one, call a San Diego treatment center to speak with a counselor about what you should do to get your loved one in for an assessment. Do this quickly as sudden changes may indicate a person in physical distress, headed for a heart attack, stroke, or other medical issues, regardless of age.

Call Us to Get Help Fast When You Need It.

Pacific Bay Recovery can help you with any substance addiction and/or mental issue you might have so you can regain a happy and functional lifestyle again. Call us for a free consultation and to set up an appointment to start getting help as soon as possible. 619-350-8220.

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