An example of cytisine overdose with no consequent side-effects: a case report

Cytisine is an alkaloid that is molecularly similar to nicotine and it is commonly used to treat smoking cessation. While it is considered a reasonably safe treatment option, cytisine intoxication in humans exhibits several adverse effects. These involve the gastrointestinal system (nausea, vomiting, diarrhea), the central nervous system (drowsiness, fatigue, delirium), and the motor system (muscle twitching and fasciculation, difficulties in walking).

We present a unique case report in which a Caucasian patient (an Italian 64-year-old woman) who was undergoing smoking cessation treatment with cytisine, and due to her misunderstanding of the therapeutic indications provided, took twice the recommended dose every day for 8 days, leading to an intake of 54 mg/dl of cytisine for 3 consecutive days. Notwithstanding the high dosage, the patient did not report any adverse reactions.

This confirms the safety of the drug, even at high doses, in patients aiming to quit smoking.