Psychological Effects of Fentanyl

Doctors prescribe fentanyl--a type of opioid pain medication--to patients with cancer, according to 12. Available forms of fentanyl include a patch attached to the skin, lozenge, tablet and soluble film. The American Cancer Society says fentanyl works by binding to opioid receptors located in the brain, which reduces how a person experiences pain. Because fentanyl affects the brain, it can result in psychological effects 1.

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Mood Changes

The American Cancer Society says patients who use fentanyl can have mood changes. For example, some patients may feel euphoric after using fentanyl. They may also have an increased sense of well-being. Other patients may have depression that features crying spells, even thinking about death. Depression can also result in behavioral symptoms, such as changes in appetite and sleep. Irritability may also occur from fentanyl use.

Anxiety says fentanyl users may become anxious when they use this drug 12. With anxiety, a person has overwhelming fear or nervousness, which can affect their daily activity. For example, people with anxiety may avoid doing certain activities that make them nervous, such as driving. Anxiety can also cause decreased concentration and confusion, which makes it difficult to think clearly. MedlinePlus points says anxiety can result in physical symptoms, including dizziness, abdominal pain, trembling, headaches, rapid breathing and sweating 3. The anxiety from fentanyl may affect users' sleeping patterns, such as causing problems falling asleep.


The American Cancer Society says that while rare, fentanyl can cause hallucinations. During a hallucination, the person believes what she perceives is real. MedlinePlus notes that auditory hallucinations, the most common type of hallucination, can result in people hearing voices 4. The tone and message of these voices can vary. For example, if a person has an auditory hallucination while depressed, she may hear voices telling her to kill herself. For other people, the auditory hallucinations may compliment them. Some people with auditory hallucinations may hear sounds such as music or clapping. Visual hallucinations, the other type of hallucination that may occur with fentanyl use, cause people to see objects that do not exist, or even patterns of lights.