Signs and Symptoms of Drug Use

There are many signs, both physical and behavioral, that indicate drug use. Each drug has its own unique manifestations, but there are some general indications that a person is using drugs:

  • Sudden change in behavior
  • Mood swings; irritable and grumpy and then suddenly happy and bright
  • Withdrawal from family members
  • Careless about personal grooming
  • Loss of interest in hobbies, sports and other favorite activities
  • Changed sleeping pattern; up at night and sleeping during the day
  • Red or glassy eyes
  • Sniffly or runny nose

The following are effects related to frequently used drugs and also links to pages on the signs and symptoms of specific drug use:

Methamphetamine Effects

“Wired”–sleeplessness for days and weeks at a time, total loss of appetite, extreme weight loss, dilated pupils, excited, talkative, deluded sense of power, paranoia, depression, loss of control, nervousness, unusual sweating, shaking, anxiety, hallucinations, aggression, violence, dizziness, mood changes, blurred vision, mental confusion, agitation.

Ecstasy Effects

Changes in mental and physical stimulation, altered perception of sound, light, touch. Stimulation of physical energy with related decrease in appetite and increase in body temperature. Increase in emotional response and sensual reactions. Teeth clenching, muscle cramping, nausea, chills and sweating. Body may overheat which can lead to fatalities.

Cocaine Effects

Impaired thinking, confused, anxious, depressed, short tempered, panic attacks, suspiciousness, dilated pupils, sleeplessness, loss of appetite, decreased sexual drive, restlessness, irritability, very talkative, scratching, hallucinations, paranoia.

Also, get information on crack cocaine use on this page.

LSD (Acid) Effects

Dilated pupils, skin discoloration, loss of coordination, false sense of power, euphoria, distortion of time and space, hallucinations, confusion, paranoia, nausea, vomiting, loss of control, anxiety, panic, helplessness, and self-destructive behavior.

PCP Effects

Sometimes violent or bizarre behavior (suicide has often occurred), paranoia, fearfulness, anxiety, aggression, acting withdrawn, skin flushing, sweating, dizziness, total numbness, and impaired perceptions.

Inhalant Effects

Short-term euphoria, giggling, silliness, dizziness, followed by headaches and fainting or unconsciousness. Long-term use: Memory loss, emotional instability, impairment of reasoning, slurred speech, clumsy, staggering gait, eye flutter, tremors, hearing loss, loss of sense of smell, and escalating stages of brain atrophy. Sometimes these serious long-term effects are reversible with body detoxification and nutritional therapy; sometimes the brain damage is irreversible or only partially reversible.

Heroin Effects

Chemically enforced euphoria, a dreamlike state similar to sleep in which the person can drift off for minutes or hours at a time. For long-time abusers, heroin may act like a stimulant, and they can perform a normal daily routine. Others may find themselves completely powerless to do anything.

Methadone: Methadone Use Signs and Symptoms

Marijuana Effects

Compulsive eating, bloodshot and squinty red eyes (may have trouble keeping them open), dry mouth, excessive and uncontrollable laughter, forgetfulness, short-term memory loss, extreme lethargy, delayed motor skills, occasional paranoia, hallucinations, laziness, lack of motivation, stupidity, sickly sweet smell on body, hair and clothes, and strong mood changes and behaviors when the person is “high.”

Depressants (Tranquilizers and Barbiturates)

Decreased inhibition, slowed motor coordination, lethargy, relaxed muscles, staggering gait, poor judgment, slow or uncertain reflexes, disorientation, slurred speech.


For additional assistance in determining if someone is abusing drugs, contact a Narconon drug rehab counselor at a center near you. They can help you.

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