Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0030193 (pain)
 261,466 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The subjective, psychomotor, and physiological effects of analgesic doses of oral codeine and morphine were examined in 12 healthy volunteers. Subjects ingested placebo, morphine 20 or 40 mg, or codeine 60 or 120 mg in a randomized, double-blind, crossover design. The smaller and larger doses of each drug were putatively equianalgesic, and the cold-pressor test was included to test this assumption. Codeine and morphine increased ratings of "feel drug effect" but had little effect on other subjective measures, including the Addiction Research Center Inventory, visual analog scales, and adjective checklists. The few subjective effects that were observed were modest and were dose-related for morphine but not for codeine. The drugs did not affect performance on Maddox-Wing, digit-symbol substitution, coordination, auditory reaction, reasoning, and memory tests. Dose-related decreases in pupil size (miosis) were observed following codeine and morphine. Ratings of pain intensity decreased in a dose-related manner for morphine but not for codeine. Plasma codeine and morphine levels varied as an orderly function of dose. These results suggest that oral codeine and morphine are appropriate drugs for outpatient pain relief because they are effective analgesics at doses that have only modest effects on mood, produce few side effects, and do not impair performance. The results also suggest a possible ceiling effect of codeine on analgesia and subjective effects.
 ...
PMID:Subjective, psychomotor, and analgesic effects of oral codeine and morphine in healthy volunteers. 986 Jan 10

The antinociceptive effects of various mu opioids given p.o. alone and in combination with Delta-9-tetrahydrocannabinol (Delta9-THC) were evaluated using the tail-flick test. Morphine preceded by Delta9-THC treatment (20 mg/kg) was significantly more potent than morphine alone, with an ED50 shift from 28.8 to 13.1 mg/kg. Codeine showed the greatest shift in ED50 value when administered after Delta9-THC (139.9 to 5.9 mg/kg). The dose-response curves for oxymorphone and hydromorphone were shifted 5- and 12.6-fold, respectively. Methadone was enhanced 4-fold, whereas its derivative, l-alpha-acetylmethadol, was enhanced 3-fold. The potency ratios after pretreatment with Delta9-THC for heroin and meperidine indicated significant enhancement (4.1 and 8.9, respectively). Pentazocine did not show a parallel shift in its dose-response curve with Delta9-THC. Naloxone administration (1 mg/kg s.c.) completely blocked the antinociceptive effects of morphine p.o. and codeine p.o. The Delta9-THC-induced enhancement of morphine and codeine was also significantly decreased by naloxone administration. Naltrindole (2 mg/kg s.c.) did not affect morphine or codeine antinociception but did block the enhancement of these two opioids by Delta9-THC. No effect was seen when nor-binaltorphimine was administered 2 mg/kg s.c. before morphine or codeine. Furthermore, the enhancements of morphine and codeine were not blocked by nor-binaltorphimine. We find that many mu opioids are enhanced by an inactive dose of Delta9-THC p.o. The exact nature of this enhancement is unknown. We show evidence of involvement of mu and possibly delta opioid receptors as a portion of this signaling pathway that leads to a decrease in pain perception.
 ...
PMID:Enhancement mu opioid antinociception by oral delta9-tetrahydrocannabinol: dose-response analysis and receptor identification. 1021 64

Although codeine is a widely used medication, the problems of codeine abuse and dependence have not been well-studied. This study characterized regular codeine users (using at least 3 days per week for 6 months, excluding those using codeine for the treatment of cancer pain) through a self-completed questionnaire. Recruitment through newspaper advertisements resulted in a total of 339 eligible questionnaires. Thirty-seven percent of subjects met DSM-IV criteria for codeine dependence. Dependent subjects (mean age, 40 +/- 10 years) were using an average of 179 (+/-171) mg of codeine per day. Codeine was predominantly used in the form of combination products with acetaminophen. Dependent subjects identified specific problems causally related to their codeine use such as depression (23%), anxiety (21%), and gastrointestinal disturbances (13%). The dependent subjects reported problems with other drugs more than did nondependent users (alcohol, 57% vs. 26%; cannabis, 23% vs. 5%; sedative/hypnotics, 33% vs. 12%; and heroin, 11% vs. 2%, respectively). Most were taking codeine primarily for a chronic pain problem (81%), although the dependent subjects currently found codeine less effective for treating pain than did the nondependent subjects and were more likely to use codeine for pleasurable effects, to relax, or to prevent withdrawal symptoms. This study showed that dependence is associated with the regular use of codeine. Pain is a key issue with these users; however, they are probably not receiving optimal treatment. There is a need to identify individuals experiencing problems with their codeine use and to develop optimal prevention and treatment strategies.
 ...
PMID:Characteristics of dependent and nondependent regular users of codeine. 1044 Apr 66

Concern has been raised that the barbiturate component of barbiturate-containing analgesics constitutes a public and individual health problem because of information from literature before 1966 concerning preclinical and clinical abuse liability, and the dependence risk of barbiturates. The safety of barbiturates alone and in combination in analgesics was reviewed. In addition, information from manufacturers of combination products were evaluated. A meta-analysis was not possible because of the paucity of formal clinical trials. Even though barbiturates have a narrow margin of safety and substantial abuse potential, there is no evidence that barbiturate-containing analgesics without codeine represent a public health or social problem because of their abuse potential. However, proper studies to confirm this theory have not been performed. In the absence of better data concerning efficacy and lack of dependence potential, barbiturate-containing analgesics are not first-line medications for the initiation of treatment for pain. Codeine-containing combination analgesics have the potential to be a more important public health problem than those with only barbiturate in the combination.
 ...
PMID:Risk of drug dependence and abuse posed by barbiturate-containing analgesics. 1046 62

Codeine is frequently used for postoperative analgesia in children. Intramuscular injections are not ideal and the rectal route may be preferable. We compared rectal and intramuscular codeine administered following neurosurgery. 20 children (over 3 months) undergoing elective neurosurgical procedures, were randomized to receive either rectal or intramuscular codeine phospate (1 mg.kg-1) at the end of the procedure. Serum levels of codeine and morphine were assayed at intervals following administration (0, 30, 60, 120, 240 min). Fentanyl was the intraoperative analgesic and postoperative rescue analgesia was paracetamol, diclofenac and intramuscular codeine. The Children's Hospital of Eastern Ontario Pain Scale was used to assess analgesia. Peak codeine levels in both groups were observed at 30 min and morphine levels were consistently low. The plasma codeine levels were significantly greater at 30 and 60 min following intramuscular injection, and were associated with slightly better analgesia scores, but did not reach statistical significance. However, the peak plasma level occurred at similar times in both groups. Codeine is absorbed as rapidly via the rectal route compared with the intramuscular route but the peak levels are lower.
 ...
PMID:A comparison of rectal and intramuscular codeine phosphate in children following neurosurgery. 1073 83

The hypoalgesic effect of single oral doses of 100 mg imipramine and 125 mg codeine was evaluated in a randomised, placebo-controlled, double-blind, 3-way cross-over experiment including 18 healthy volunteers. Pain tests were performed before and 90, 180, 270, 360 and 450 min after medication. The tests included determination of pain tolerance thresholds to pressure, pain detection/tolerance thresholds to single electrical sural nerve stimulation and pain summation at tolerance threshold to repetitive electrical sural nerve stimulation (temporal summation) and pain experienced during the cold pressor test, rated as peak pain intensity, pain average intensity and discomfort. Compared to placebo, imipramine significantly increased pressure pain tolerance threshold (P = 0.03) and increased pain tolerance threshold (P = 0.05) and pain summation threshold (P = 0.03), but not pain detection threshold to electrical stimulation. Imipramine did not cause significant changes in pain perception during the cold pressor test. Codeine significantly increased pressure pain tolerance threshold (P = 0.02), pain detection (P = 0.04) and pain tolerance threshold (P = 0.01) and pain summation threshold (P = 0.02) to electrical stimulation. In addition, codeine reduced the pain experienced during the cold pressor test (P = 0.04-0.003). It is concluded that both imipramine and codeine inhibit temporal pain summation, whereas only codeine reduces cold pressor pain. Pain summation may be a key mechanism in neuropathic pain. Imipramine has a documented effect on such pain conditions on temporal summation. The present study showed that codeine also inhibits temporal summation, which is in line with the clinical observations indicating that opioids relieve neuropathic pain.
Pain 2001 May
PMID:The analgesic effect of codeine as compared to imipramine in different human experimental pain models. 1132 49

This study analyzes the combination of oral ketorolac 10 mg with varying amounts of codeine phosphate, and the postoperative pain relief that developed from these combinations. Five groups of patients were administered the codeine/ketorolac combinations. Variations of the combinations were analyzed to ascertain if an optimal analgesic ratio existed. All controllable variables involved with the surgical procedure were held constant to allow for better evaluation of postoperative pain. Results obtained from 67 patients indicated that the best pain relief was achieved with a combination of 10 mg ketorolac and 15 mg codeine phosphate. Codeine alone provided adequate analgesia, but the addition of ketorolac reduced the patients' perceived side effects. The presence of codeine in the analgesic combination was also shown to reduce the number of days that the patient required the medication postoperatively. Reducing the duration of medication use postoperatively may also minimize the possible side effects of ketorolac and codeine, which could develop with extended periods of use.
 ...
PMID:Evaluation of ketorolac (Toradol) with varying amounts of codeine for postoperative extraction pain control. 1219 Jan 34

This study was designed to evaluate the extent of the antinociceptive interaction between codeine and diclofenac at the local, spinal and systemic level. The effects of individual and fixed-ratio combinations of locally, spinally or orally given codeine and diclofenac were assayed using the formalin test in rats. Isobolographic analysis was employed to characterize the synergism produced by the combinations. Codeine, diclofenac and fixed-ratio codeine-diclofenac combinations produced a dose-dependent antinociceptive effect when administered locally, spinally or systemically. ED(30) values were estimated for the individual drugs and isobolograms were constructed. Theoretical ED(30) values for the combination estimated from the isobolograms were 422.2+/-50.5 microg/paw, 138.5+/-9.2 microg/rat, and 9.3+/-1.1 mg/kg for the local, spinal and oral routes, respectively. These values were significantly higher than the actually observed ED(30) values which were 211.1+/-13.6 microg/paw, 45.9+/-3.9 microg/rat, and 2.5+/-0.2 mg/kg, indicating a synergistic interaction. Systemic administration resulted in the highest increase in potency, being about fourfold, while spinal and local administration increased potency in two- and threefold, respectively. The fact that the highest synergism was observed after systemic administration suggests that the interaction is occurring at several anatomical sites. The results support the clinical use of this combination in pain management.
 ...
PMID:Synergistic effects between codeine and diclofenac after local, spinal and systemic administration. 1464 45

(1) The first-line drugs for mild to moderate pain are non opiate analgesics, namely paracetamol and nonsteroidal antiinflammatory drugs (NSAIDs). (2) Codeine, dextropropoxyphene and tramadol are weak opiates; they are often used with paracetamol in fixed-dose combinations, in order to reinforce the analgesic effect of paracetamol. (3) These analgesic combinations have only been evaluated in a few situations associated with chronic and acute pain. And the endpoints used in clinical trials are designed more to show statistically significant differences than clear clinical differences. (4) In acute pain, available meta-analyses confirm that the first-line drug is paracetamol, or, if necessary, ibuprofen, a NSAID. (5) The paracetamol + codeine combination slightly increases the analgesic effect of paracetamol, but causes more adverse effects. Combinations of paracetamol + dextropropoxyphene and paracetamol + tramadol are even less useful. (6) The few available clinical trials fail to demonstrate that combining paracetamol with a NSAID is any more effective than either drug given alone, while adverse effects are increased. (7) Paracetamol is also the first-line treatment for chronic non cancer pain, such as low back pain or pain due to osteoarthritis of the hip. NSAIDs have no advantages over paracetamol in these settings. We found no trials of paracetamol + NSAID combinations. Combinations of paracetamol and weak opiates have been inadequately studied in this situation, and are only second-line options.
 ...
PMID:Weak opiate analgesics: modest practical merits. 1505 24

Butorphanol tartrate is a synthetic mixed agonist-antagonist opioid analgesic. Its transnasal dosage form, which may be self-administered when the use of an opioid analgesic is appropriate, was previously shown to provide rapid relief of migraine pain. In this double-blind, parallel-group, outpatient study, we compared butorphanol nasal spray 1 mg followed in 1 hour by an optional second 1-mg dose with the orally administered analgesic, Fiorinal with Codeine (one capsule containing butalbital 50 mg, caffeine 40 mg, aspirin 325 mg, and codeine phosphate 30 mg). Patients (N=321) were assigned by randomization to one of two treatment groups (butorphanol or Fiorinal with Codeine) and instructed to self-administer medication when migraine pain reached an intensity of moderate or severe and to record study-related events in a diary for 24 hours posttreatment. Efficacy analyses were performed on data from 275 patients who took study medication and returned a patient diary; 136 in the butorphanol group and 139 in the Fiorinal with Codeine group. During the first 2 hours after treatment, butorphanol was more effective than Fiorinal with Codeine in treating migraine pain as measured by pain intensity difference scores, percentage of responders (pain decreased to mild or none), percentage of pain-free patients, and degree of pain relief, with a more rapid time to onset of 15 minutes. A similar percentage of patients in the two groups used rescue medication during the first 4 hours, after which more butorphanol-treated than Fiorinal with Codeine-treated patients used rescue medication. Butorphanol patients had more side effects, less improvement in digestive symptoms, and less improvement in functional ability than Fiorinal with Codeine patients.
 ...
PMID:Comparison of butorphanol nasal spray and fiorinal with codeine in the treatment of migraine. 1856 49


<< Previous 1 2 3 4 5 6 7 8 Next >>