Doxepin is the generic form of the brand name tricyclic antidepressant doxepin. Doxepin is unique among tricyclics because its therapeutic effects vary greatly depending on dose. At low doses, Silenor can be used to treat mild insomnia and allergic reactions. Doxepin is sold as a topical ointment to reduce skin inflammation caused by histamine reactions. At slightly higher daily doses, Silenor can become an effective anxiolytic (anxiety-reducer) and antidepressant, especially in patients dealing with alcohol addiction.

Cases of doxepin misuse and addiction are rare. The general effects of doxepin don’t make it an appealing substance to misuse. Silenor is classified as “non-addictive” by the federal government.

Silenor can trigger a wide range of anticholinergic and central nervous system (CNS) side effects. Anticholinergic side effects may include profuse sweating, constipation, difficulty urinating and dry mouth. Doxepin can impact the central nervous system by inducing drowsiness, confusion, agitation, difficulty sleeping, fatigue, lightheadedness and dizziness. On rare occasions, treatment with doxepin can result in seizures, delirium and tinnitus (ringing in the ears). Other side effects may include low blood pressure, rapid heart rate and abnormal heart rhythms. Silenor may decrease liver function in some patients.

What Is Silenor (Doxepin)?

Tricyclic antidepressants like Silenor achieve their effects by increasing the activity of several critical neurotransmitters in the brain. Doxepin focuses primarily on boosting levels of serotonin and norepinephrine. Deficiencies in these neurotransmitters have been closely linked to an increased risk for depression and anxiety.

Doxepin reduces anxiety and depression by inhibiting the reuptake of serotonin and norepinephrine from the synaptic gap between neurons. The longer these neurotransmitters can stay in the synaptic gap, the longer they can induce beneficial effects and reduce symptoms.

Silenor also acts on acetylcholine, the primary neurotransmitter of the prefrontal cortex. The prefrontal cortex is the area of the brain responsible for critical thinking. Doxepin’s ability to minimize allergic reactions is thanks to its activity on histamine receptors in the body

Silenor (Doxepin) Addiction

The US government classifies doxepin as non-addictive. Doxepin is not considered addictive because it does not trigger increased cravings for the drug when treatment is stopped. However, two other tricyclics, amineptine and tianeptine, have a much higher misuse potential. Researchers suspect that these tricyclics are more addictive due to their preferential targeting of another critical neurotransmitter, dopamine. When cases of addiction occur, they usually involve patients who have a history of substance misuse disorders such as alcoholism or opioid addiction.

Silenor (Doxepin) Long-Term Effects

Patients can begin to develop a tolerance for Silenor because of long-term use, leading to a gradual or sudden decrease in the drug’s effectiveness. Silenor is metabolized by the liver. Patients with a history of liver conditions may experience decreased liver function over time. When doxepin becomes ineffective, your doctor may decide to discontinue treatment.

Although doxepin is considered non-addictive, cessation of use can trigger withdrawal-like symptoms referred to as discontinuation syndrome. Discontinuation of Silenor may result in increased insomnia, anxiety, malaise, nausea, headache or motor disturbances. Notify your doctor as soon as you experience the onset of such symptoms.

Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.