Date of Award


Degree Type

Selective Evidence-Based Medicine Review

Degree Name

Master of Science in Health Sciences - Physician Assistant

Department Chair

John Cavenagh, PhD, PA-C


OBJECTIVE: The objective of this selective EBM review is to determine whether or not nicotine replacement therapy reduces the withdrawal symptom of craving, or urge to smoke, in dependent adult smokers during smoking cessation.

STUDY DESIGN: Systematic review of three English language and peer-reviewed randomized-controlled trials published in 2009, 2010, and 2011.

DATA SOURCES: One single-blinded randomized-controlled crossover trial, one double-blinded, placebo controlled, randomized-controlled crossover trial, and one single-blinded, placebo controlled, randomized-controlled crossover trial

OUTCOMES MEASURED: Withdrawal symptoms of craving, irritability, difficulty concentrating, and restlessness were measured on a 100mm visual analog scale (VAS). Adverse effects (AEs) of mouth and throat irritation, aching jaw, feeling sick, vomiting, flatulence/belching, stomachache, heartburn, diarrhea, hiccups, feeling high, feeling dizzy, headache, palpitations, sweatiness, and cold hands/feet were measured based upon their frequency and strength. One study measured slightly different withdrawal symptoms (depressed mood, irritability, restlessness, hunger, and poor concentration) on a Moods and Physical Symptoms Scale (MPSS) and time spent with urges and strength of urges on a six-point Likert Scale. This study also measured the adverse effects of feeling unwell, nausea, throat irritation, and dizziness on a 10-point scale. Temporary smoking cessation was measured in all three studies.

RESULTS: Thornley et al found that the active pouch significantly decreased craving in comparison to placebo. The gum decreased craving; however, the findings were not considered to be statistically significant. In McRobbie et al, all three types of NRT proved to significantly decrease craving in comparison to placebo. Similarly, Shahab et al found that both innovative and older types of NRT decreased craving. The Nicotine Cannon was more tolerable than older types of NRT. Overall, the NRT products caused more adverse reactions than placebo, but also led to more cases of temporary smoking cessation.

CONCLUSION: The results of all three studies show that nicotine replacement therapy decreases the withdrawal symptom of craving, allowing smokers to be more successful in their attempts to quit in the short term. No one NRT product is significantly better than another in decreasing craving.