Tolerance of pain

The end result of these differences, although apparent rather than real, may be why the recommended dose of captopril (an ACE Inhibitor, antihypertensive drug) is 75—450 mg per day in the United States and 37.5-122.5 mg per day in Japan (with overall adverse events of 39% and 3.8% respectively). With a nonsteroidal antiinflammatory agent, overall adverse events were 45-51 % in the United States and 24% in Japan at the same dosage however, efficacy was the same (Dziewanowska, 1992). In general, the British, Dutch and Scandinavian data are closer to those observed in the United States, with the German and Swiss data least reactive and French, Italian and Spanish in between. As mentioned previously, severe ADRs in clinical studies tend to be the same the major difference was in minor adverse events, such as nausea, headache and so on. Thus, national temperament also may play a part in the expectation of efficacy and ADR. This finding was reflected in a study of attitudes of 4000 nurses from 13 countries to ethnic tolerance of pain... 

Chronic pain, by its persistent and pathological form, appears to have no biological function. It imposes physical, emotional, and social stresses of severe magnitude. The patient s response to chronic pain is very different than to acute pain. Physical deterioration is often seen, and is actually aggravated by resorting to excessive medication. There is some indication that the pain threshold—and therefore tolerance of pain—actually decreases, possibly due to a depletion of endorphins.1 In some cases the underlying pathology, if any, for chronic pain cannot be found. 

The scientific evidence of work-relatedness of musculoskeletal disorders has been firmly established by numerous epidemiologic studies conducted over the last 25 years of research in the field (NIOSH 1997). It has also been noted that the incidence and prevalence of musculoskeletal disorders in the reference populations were low, but not zero, most likely indicating the nonwork-related causes of these disorders. It was also documented that such variables as cultural differences, psychosocial and economic factors, which may influence one s perception and tolerance of pain and consequently affect the willingness to report musculoskeletal problems, may have significant impact on the progressions from disorder to work disability (WHO 1985 Leino 1989). 

Episodes of ischemia may also be painless, or silent, in at least 60% of patients, perhaps due to a higher threshold and tolerance for pain than in patients who have pain more frequently. 

Johnson JR, Bumell-Nugent M, Lossignol D, Ganae-Motan ED, Potts R, Fallon MT. (2010) Multicenter, double-blind, randomized, placebo-controlled, parallel-group study of the efficacy, safety, and tolerability of THC CBD extract and THC extract in patients with intractable can correlated pain. J Pain Symptom Manage 39 167-179. 

Tolerance. With repeated administration of opioids, their CNS effects can lose intensity (increased tolerance). In the course of therapy, progressively larger doses are needed to achieve the same degree of pain relief Development of tolerance does not involve the peripheral effects, so that persistent constipation during prolonged use may force a discontinuation of analgesic therapy however urgently needed. 

Adults 2.5 to 10 mg IV, IM, subcutaneously, or orally every 3 or 4 hours as necessary. Adjust dosage according to the severity of pain and patient response. For exceptionally severe pain, or in those tolerant of narcotic analgesia, it may be necessary to exceed the usual recommended dosage. 

IR tablets - For the management of moderate to severe pain in patients who require treatment with an oral opioid analgesic. Individually adjust the dose according to severity of pain, patient response, and patient size. If the pain increases in severity, analgesia is not adequate, or tolerance occurs, a gradual increase in dosage may be required. 

Acute gouty arthritis-50 mg 3 times/day until pain is tolerable, then rapidly reduce the dose to complete cessation of the drug. Definite relief of pain usually occurs within 2 to 4 hours. Tenderness and heat usually subside in 24 to 36 hours, and swelling gradually disappears in 3 to 5 days. Do not use sustained-release form. 

Patients with known history of tolerance - The mean dose administered to patients in the phase 3 study was 236 units (25% to 75% range, 198 units to 300 units). The dose was divided among the affected muscles. Tailor dosing in initial and sequential treatment sessions to the individual patient based on the patient s head and neck position, localization of pain, muscle hypertrophy, patient response, and adverse event history. 

Opioid All levels of pain intensity Drowsiness Tolerance... 

It is indicated in the treatment of a variety of painful inflammatory conditions, including osteoarthritis, oncology, postopera-tively, trauma, sports injuries, ear, nose and throat disorders, dental surgery, bursitis/ tendinitis, thrombophlebitis, upper airways inflammation and gynaecological disorders. Nimesulide has shown to be well tolerated even by aspirin sensitive asthmatic patients. 

At the present time, the TCAs are used primarily in depression that is unresponsive to more commonly used antidepressants such as the SSRIs or SNRIs. Their loss of popularity stems in large part from relatively poorer tolerability compared with newer agents, to difficulty of use, and to lethality in overdose. Other uses for TCAs include the treatment of pain conditions, enuresis, and insomnia. 

In addition to the development of tolerance, persistent administration of opioid analgesics has been observed to increase the sensation of pain leading to a state of hyperalgesia. This phenomenon has been observed with several opioid analgesics, including morphine, fentanyl, and remifentanil. Spinal dynorphin and activation of the bradykinin receptor have emerged as important candidates for the mediation of opioid-induced hyperalgesia. 

Unfortunately, the inconvenience occasioned by these laws—and an unwarranted fear by medical professionals themselves regarding the risk of patient tolerance and addiction—continues to hamper adequate treatment of patients with terminal conditions. This has been shown to be particularly true in children and elderly patients with cancer. There is no excuse for inadequate treatment of pain in a terminal patient not only is addiction irrelevant in such a patient, it is actually uncommon in patients who are being treated for pain (see Chapter 31). 

A brief rest period was inserted between the exercycling and the experimental cold-pressor trial. This interval gave the experimenter the opportunity to present the correlational structure discussed previously. To prevent subjects from discovering the true purpose of the study, the crucial information was embedded in a mini-lecture on psychophysics. Subjects learned that the cold-pressor was used to study the psychophysics of pain. Psychophysics was defined as the attempt to relate mathematically the perception of a stimulus to the physical properties of a stimulus. Subjects were shown a curve on a blackboard that related time of immersion in cold water to subjective discomfort (i.e., numbers from one to ten). The curve depicted the typical relationship and it was said to be based on data averaged over many people. Individual differences were said to exist, illustrated by showing two curves that reached ten at different rates. Skin type was said to be one factor that distinguished between people with high or low tolerance to cold water. Heart type was said to be another factor. 

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