ABSTRACT
Previous pharmacological studies using animals indicated that a systemic administration of L-threo-3,4-dihydroxy-phenylserine (L-DOPS), a precursor of noradrenaline, induces an antinociceptive effect and an increase in the CNS level of noradrenaline which serves an inhibitory role at the spinal dorsal horn and the supraspinal pain afferent system. The aim of the present study was to investigate the analgesic effect of L-DOPS in patients with chronic pain. We selected 18 patients with various kinds of pain. In nine patients, L-DOPS (tablets) was orally administered and pain was assessed by the visual analogue scale (VAS) before and after the L-DOPS administration. Administration of L-DOPS resulted in dose-dependent analgesia. The maximum analgesia (VAS change: from 10 to 4.1 +/- 0.9) was observed 60 min after an administration of 100 mg and it lasted for 2-5 h depending on the patient. In the other nine patients, oral administration of placebo tablets produced only a slight analgesia (VAS change: from 10 to (9.2 +/- 0.3). The difference between the L-DOPS-induced effect and the placebo-induced one was statistically significant. After repeated administration of L-DOPS for 4-5 weeks, neither tolerance nor side effects were observed.
Subject(s)
Droxidopa/therapeutic use , Pain/drug therapy , Administration, Oral , Adult , Aged , Droxidopa/administration & dosage , Female , Humans , Male , Middle Aged , Time FactorsABSTRACT
Our previous pharmacological studies using animals indicated that a systemic administration of L-arginine induces an antinociceptive effect and an increase in the brain level of kyotorphin (L-tyrosinyl-L-arginine) which is an endogenous analgesic peptide and a methionine-enkephalin releaser in the brain. The aims of this study were to investigate the analgesic effect of L-arginine, a precursor of kyotorphin, in persistent pain. We selected 12 patients with various kinds of pain of at least 6 months duration. L-Arginine (10% solution, 300 ml (30 g)/patient) was administered by intravenous drip at a rate of 5 ml (0.5 g)/min during a period of 60-70 min. Pain was assessed by the patient using a 10-cm visual analogue scale (VAS), before and after the L-arginine infusion. L-Arginine treatment resulted in slight analgesia at 10-15 min after the onset of infusion and in marked analgesia at 30-40 min after that. This effect lasted for 6-24 h. L-Arginine-induced analgesia was dose-dependent and blocked by intravenous injection of naloxone. In each case, the L-arginine-induced analgesia was statistically significant as compared with the saline-induced effect. Side effects of L-arginine were a slight decrease in mean blood pressure (10-15 mm Hg), and dryness of the month. A suppressive role of a functional link between the L-arginine-kyotorphin system and the enkephalin system of the brain in persistent pain is suggested.
Subject(s)
Analgesics/therapeutic use , Arginine/therapeutic use , Pain/drug therapy , Aged , Arginine/adverse effects , Arginine/antagonists & inhibitors , Chronic Disease , Cluster Headache/drug therapy , Dose-Response Relationship, Drug , Female , Humans , Infusions, Intravenous , Male , Middle Aged , Naloxone/pharmacology , Pain MeasurementABSTRACT
The continuous subcutaneous infusion of buprenorphine, a new approach to the relief of severe cancer pain, has been carried out using a portable infusion pump. The efficacy of this method was examined in 30 patients by visual analogue scale. An infusion rate of 4 micrograms/kg/day following intramuscular administration of 0.004 micrograms/kg gave satisfactory pain relief without serious complications. The minimum effective blood concentration was not detectable by high-performance liquid chromatography. Advantages of this therapy are its simplicity, applicability in many types of cancer, multiple sites of administration, and easier training on the part of health personnel.
Subject(s)
Buprenorphine/therapeutic use , Neoplasms/physiopathology , Pain, Intractable/drug therapy , Adult , Aged , Blood Pressure/drug effects , Buprenorphine/administration & dosage , Buprenorphine/adverse effects , Female , Humans , Infusion Pumps , Injections, Subcutaneous , Male , Middle Aged , Pain MeasurementABSTRACT
The efficacy of continuous subcutaneous infusion of buprenorphine for the treatment of terminal cancer pain was studied. Continuous subcutaneous administration of 4-8 micrograms/kg/day of buprenorphine, examined by the visual analogue scale was revealed to have satisfactory analgesic potency for control of every type of terminal cancer. This therapy can be undertaken by any member of the medical staff because of its safety and simplicity. The indications for this method are almost unlimited when the subcutaneous tissue can absorb the drug at a constant rate. Continuous subcutaneous buprenorphine administration via a portable infusion pump allows patients with severe pain from cancer the opportunity to move about freely.
