Hooten WM, Mantilla CB, Sandroni P, Townsend CO Associations between heat pain perception and opioid dose among patients with chronic pain undergoing opioid tapering. Pain Med. 2010 Nov;11(11):1587-98. doi: 10.1111/j.1526-4637.2010.00962.x. Epub 2010 Oct
Katz NP, Paillard FC, Edwards RR Review of the performance of quantitative sensory testing methods to detect hyperalgesia in chronic pain patients on long-term opioids. Anesthesiology. 2015 Mar;122(3):677-85. doi: 10.1097/ALN.0000000000000530.
Pud D, Cohen D, Lawental E, Eisenberg E Opioids and abnormal pain perception: New evidence from a study of chronic opioid addicts and healthy subjects. Drug Alcohol Depend. 2006 May 20;82(3):218-23. doi: 10.1016/j.drugalcdep.2005.09.007. Epub 2005 Oct 17
Suzan E, Eisenberg E, Treister R, Haddad M, Pud D A negative correlation between hyperalgesia and analgesia in patients with chronic radicular pain: is hydromorphone therapy a double-edged sword? Pain Physician. 2013 Jan;16(1):65-76.
Wright A, Benson HAE, Will R, Moss P Cold Pain Threshold Identifies a Subgroup of Individuals With Knee Osteoarthritis That Present With Multimodality Hyperalgesia and Elevated Pain Levels. Clin J Pain. 2017 Sep;33(9):793-803. doi: 10.1097/AJP.0000000000
Quantitative Sensory Testing in Chronic Pain Patients Undergoing Opioid Treatment and Opioid Tapering
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.