Design: Smokers were assessed one week before stopping smoking (baseline), then after one, two, and six weeks of smoking abstinence.
Participants: 174 smokers attending a seven week smoking cessation programme combining behavioural support with nicotine patches.
Main outcome measures: Self reports of cold symptoms, mouth ulcers, and smoking abstinence (validated using expired carbon monoxide) were recorded on each measurement occasion.
Results: Following one, two, and six weeks of smoking abstinence 73.0% (127/174), 57.5% (100/174), and 44.8% (78/174) of the participants, respectively, maintained continuous abstinence and provided reports of cold symptoms and mouth ulcers. For those abstinent from smoking for six weeks, relative to baseline, a significant increase in reports of the number of cold symptoms was observed following one and two weeks of smoking abstinence (p = 0.009 and p = 0.038, respectively) and an increase in reports of mouth ulcers after one and two weeks of abstinence (p = 0.004 and p = 0.008, respectively). Following one week of abstinence significant increases in reports of sore throat, coughing, deafness, and sneezing were observed (p = 0.049, p < 0.001, p< 0.039, and p < 0.003, respectively).
Conclusions: This is the first study to systematically document significant increases in cold symptoms and mouth ulcers following smoking cessation. Smokers should be informed that they have an increased chance of experiencing these symptoms on stopping smoking. Being psychologically prepared for these effects may reduce their impact on the attempt to stop smoking.