Most Significant Dangers

The most significant or common dangers of Chantix involve your brain and nervous system, reports the U.S. National Library of Medicine. In a few cases, these effects have resulted in suicide.

Specific Side Effects

Specific neurological and psychological side effects of Chantix include depression, mania, delusions, hallucinations, paranoia, thoughts of violence or murder, hostility, agitation, anxiety, panic and thoughts about hurting yourself.

Contraindications

Because of the psychological side effects, doctors tend to avoid prescribing Chantix for people with depression, bipolar disorder, schizophrenia or other forms of mental illness, explains the Mayo Clinic.

Warning

According to the U.S. National Library of Medicine, Chantix infrequently causes angioedema, a severe allergic reaction that causes swelling of your hands, feet and throat, which can make it difficult to breathe. Additionally, Chantix poses a risk for an allergic skin reaction known as Stevens-Johnson syndrome, a potentially fatal reaction marked by the presence of large sores.

Increased Risk

According to the Mayo Clinic, because the safety of Chantix during pregnancy has not been established, doctors restrict its use in pregnant women. Patients with kidney disorders may not be able to take Chantix due to an increased potential for side effects.

Source:

U.S. National Library of Medicine Daily Med: CHANTIX (varenicline tartrate) kit

Mayo Clinic: Varenicline (Oral Route)