Fentanyl nasal spray for the treatment of cancer pain.

INTRODUCTION: Breakthrough pain, a transitory flare of pain in patients with otherwise controlled chronic pain, has been well characterized in cancer patients but despite medical awareness, sometimes remains underdiagnosed and therefore undertreated. AREAS COVERED: Oral transmucosal fentanyl citrate (OTFC) and fentanyl buccal tablets are the first medications developed specifically for the treatment of breakthrough pain in opioid-tolerant patients. Since oral administration of fentanyl is not an option for many cancer patients, the development of intranasal fentanyl spray (INFS) emerged as a more effective method of administration. Intranasal administration of fentanyl has several advantages over the oral/gastrointestinal route and clinical trials have shown that it is superior to OTFC while being well tolerated and more acceptable by the majority of patients. EXPERT OPINION: The aim of this review is to summarize the pharmacological characteristics and data obtained from clinical studies of INFS in the past few years, and present Fentanyl Pectin Nasal Spray (PecFent), which uses an innovative delivery system and is now approved in the EU. Finally, we discuss the impact that it may have in the future management of breakthrough pain in cancer patients, because an accurate diagnosis followed by the best treatment is crucial for effective pain alleviation.