[Chronic non-cancer-related pain. Long-term treatment with rapid-release and short-acting opioids in the context of misuse and dependency]

Annually published data show a continual increase in the volume of opioid prescriptions in Germany, thus indicating an intensification of opioid therapy. The majority of opioids are prescribed to treat chronic non-cancer-related pain. On the basis of current guidelines, as well as in terms of the lack of data regarding long-term use of opioids and their effectiveness beyond a period of 3 months, this development must be viewed critically. With reference to four case reports, we discuss and evaluate opioid therapy in relation to medication misuse and the development of drug dependency. Particular emphasis is placed on the administration of rapid-release and short-acting opioid preparations, which we consider to be particularly problematic.

[The transdermal 7-day buprenorphine patch--an effective and safe treatment option, if tramadol or tilidate/naloxone is insufficient. Results of a non-interventional study]

The transdermal 7-day buprenorphine matrix patch provides a constant and user-friendly pain management when chronic musculoskeletal pain requires opioids. This analysis of clinical routine data evaluated the benefit of this treatment for patients previously receiving oral long-term treatment with weak opioids alone. Data of 310 patients previously treated with tramadol or tildate/naloxone and part of a multicentre observational study with 3295 patients were analyzed. In 89.7% of the 310 patients oral treatment with weak opioids was replaced by the 7-day buprenorphine patch due to insufficient analgesia. During treatment with the 7-day buprenorphine patch there was a clinically significant decrease of the mean pain intensity at rest during the day from 5.7 to 2.9, on physical effort during the day from 7.3 to 3.8 and at night from 5.2 to 2.3 (11-point NRS scale, p < or = 0.001). In addition, quality of life aspects such as mobility, self-reliance and quality of sleep improved, which are relevant for individual patient satisfaction with pain management. For patients with previous long-term tramadol or tilidate/naloxone treatment the switch to the 7-day buprenorphine matrix patch proved to be effective and safe for the management of chronic pain. The user-friendly 7-day application interval contributes to improving compliance and a reducing exposure to tablets.

[Postoperative pain therapy with tilidin and tilidin retard as an oral patient-controlled analgesia after uncomplicated myocardial revascularization]

OBJECTIVE

The purpose of this study was to evaluate whether or not the combination of tilidin and tilidin retard as oral patient-controlled analgesia provide a suitable pain management in patients after uncomplicated myocardial revascularization.

METHODS

We conducted a randomised phase IV study to evaluate the effectiveness of postoperative analgesia with tilidin and tilidin retard. Patients with a baseline tilidin retard and tilidin liquid demand medication (group B, 42 patients) were compared with a base line paracetamol and tramadol-HCl liquid demand medication (group A, 44 patients). All patients received the first dose of study medication at the second postoperative day after evaluation of the individual pain score using NRS (numeric rating scale).

RESULTS

Pain relief in group B was significantly better only at the second postoperative day (NRS 1,8 compared to 3,3 in group A), associated with tolerable side effects and comfortable handling.

CONCLUSION

The combination of sustained release with immediate release drugs as a patient controlled analgesia provides suitable and comfortable analgesia after myocardial bypass surgery.

[Tilidine/naloxon retard in long-term administration in chronic pain and multimorbidity. Multicenter study of long-term tolerance and effectiveness in 2 years observation]

BACKGROUND AND METHOD

335 patients (51% female, 49% male, mean age 56 years) with chronic pain and multimorbidity have been included in a multi-center 2-years' study with slow release Tilidine/Naloxone for efficacy and safety which included detailed laboratory examinations. 316 patients had already been treated with analgesics. 159 patients (47.5%) finished the study as planned, 176 patients finished the study earlier.

RESULTS

Parameters of quality of life such as persistent pain, sleep, mood and activity have improved. Tolerance has not been observed. In 85 patients (25%) adverse events had occurred (nausea, vomiting, dizziness) which are related to the study-medication. Constipation was documented in only 4 patients. After 2 years of therapy with Tilidine/Naloxone there has been no relevant changes in laboratory findings. There has been no sign of organ damage or interactions with concomitant medication.

CONCLUSION

Tilidine/Naloxone is an effective and safe analgesic (WHO II) suitable for the longterm treatment of patients with chronic pain.

Opioid consumption in Spain--the significance of a regulatory measure

OBJECTIVE

To investigate the impact of new regulatory measures on opioid consumption in Spain during the period 1985-1998.

METHODS

A search in the ECOM (Especialidades Consumo de Medicamentos) database of the Ministry of Health was made for the 1985-1998 period. This database contains information about drug preparations prescribed in primary care in the National Health System in Spain.

RESULTS

Since 1985-1998, the overall opioid consumption has increased tenfold, from 94.7 DDD (defined daily dose) per million inhabitants per day to more than 1000 DDD. For the five drugs that require a special prescription form (morphine, methadone, pethidine, tilidine and fentanyl), the consumption has increased 13.5-fold.

CONCLUSION

A huge increase in opioid consumption has occurred. In this increase, changes in supply and, to a lesser extent, regulatory measures have played an important role.

Bioavailability investigation of a new tilidine/naloxone liquid formulation compared to a reference formulation

An oral solution available as ethanol-free droplets of the fixed drug combination tilidine-HCl 50 mg/naloxone-HCl 4 mg (CAS 27107-79-5 and CAS 465-65-6, respectively; Tilidin-ratiopharm plus Tropfen) was investigated in 12 healthy volunteers together with an ethanol-containing reference preparation for comparable bioavailability. The study was conducted in an open, randomized, two-way cross-over design applying single doses of 20 droplets (equivalent to 50 mg tilidine-HCl/4 mg naloxone-HCl) of either formulation in the fasting state. The drug plasma profiles were monitored for a period of 48 h by means of LC-MS/MS for tilidine and its active metabolite nortilidine, whereas GC-MS was employed in order to determine naloxone and its phase I metabolite, 6-beta-naloxole. Maximum concentrations (Cmax) achieved were 22.28 ng/ml (tilidine) and 92.78 ng/ml (nortilidine) for the test preparation. Corresponding values for the reference preparation were 24.95 ng/ml (tilidine) and 100.73 ng/ml (nortilidine). The extent of drug absorption (AUC0-infinity) amounted to 38.83 ng h/ml and 467.63 ng h/ml for the prodrug tilidine and the metabolite nortilidine of the test preparation and corresponded well to 43.81 ng h/ml and 493.85 ng h/ml of the reference. Regarding the rate of drug absorption, essentially identical tmax and Rabs values for both tilidine and nortilidine of either preparation in addition pointed to well comparable liquid formulations and equipotent analgesia may be inferred from opioid pharmakokinetic profiles. Pharmacokinetics of the opioid antagonist naloxone and 6-beta-naloxole were also determined and resulted in well coinciding profiles for both preparations. Thus despite the fact that only minimum oral naloxone bioavailabilities were observed, plasma level monitoring of naloxone and 6-beta-naloxole allowed for demonstration of systemic exposure of opioid antagonistic compounds throughout a period of 2-3 h after oral drug administration. Due to the limited number of subjects involved, the primary aim of the study did not consist in demonstration of drug bioequivalence. Rather a comparable bioavailability between preparations was assumed if AUC and Cmax point estimators of 90% confidence intervals would be contained within a 0.80-1.20 range. The study outcome revealed that all four investigated analytes met this requirement, whilst nortilidine pharmacokinetic parameters even fulfilled commonly accepted bioequivalence criteria, i.e. inclusion of 90% confidence intervals of AUC- and Cmax-ratios within acceptance limits of 80% and 125%. Increased data variation observed with bioavailability parameters of tilidine, naloxone and 6-beta-naloxole prevented their bioequivalence demonstration based on only 12 study participants. In conclusion, single doses of two different tilidine/naloxone 50 mg/4 mg liquid formulations revealed well comparable bioavailability for all 4 analytes investigated. Both treatments were fairly well tolerated. Most frequently reported adverse events were dizziness, headache and nausea, which all recovered without sequelae and necessity of concomitant treatment.

[Long-term treatment of chronic pain with tilidine-naloxone. An analysis of 50 patients with chronic pain conditions of non-malignant origin]

METHOD

50 patients with incurable chronic pain states were treated for a period of between six months and 14 years (median: 31 months) with tilidine-naloxone, and the results of tumor recorded. Amelioration of pain was achieved in an average of 60.7% of the cases. The 16 patients of this series suffering from neuropathic pain who received a somewhat lower dose responded equally as well (60.3% amelioration) as the overall group. In 24 patients suffering from pain, the daily dose remained unchanged throughout the course of treatment, had to be increased in 19, and was reduced in seven patients. In two patients, acceptable side-effects were indicated; in no case were there any signs of drug-induced organic damage.

CONCLUSIONS

The results show that tilidine-naloxone is a highly effective opioid analgesic with a remarkably favorable benefit-risk ratio for use in long-term treatment.

[Analgesia using oral administration of tilidine naloxone for extracorporeal shockwave lithotripsy. A double blind study]

Reduction in pain perception during ESWL due to a technical modification of the lithotriptor was expected and prompted a reassessment of anaesthesia techniques for ESWL. In this study the need for analgesic treatment had to be investigated. After satisfactory preliminary results in a previous pilot study, the value of the oral combination of the anti-anxiety drug dipotassium clorazepate on the evening before ESWL together with the analgesic tilidine-naloxone before treatment was tested in a randomised double-blind study in 120 patients. In case of intolerable pain during the treatment all patients were free to ask for additional intravenous analgesic medication (fentanyl). During ESWL, 28.3% of the tilidine-N group patients and 6.7% of the placebo group were pain-free, whereas intolerable pain was reported by 30% of the tilidine-N group and 56.7% of the placebo group. Therefore, 70% of the tilidine-N group patients were treated without any additional analgesic or sedative medication. The good experience with this oral anaesthesia approach, the lack of significant side effects and a good acceptance by the patients warrant further recommendation of this technique.

Pharmacokinetics of tilidine and metabolites in man

Tilidine is a prodrug from which the active metabolite nortilidine is formed by demethylation. The pharmacokinetics of tilidine (T), nortilidine (NT) and bisnortilidine (BNT) were studied in nine healthy subjects following single intravenous (10 min infusion) and oral 50 mg T-HCl dose as well as following multiple 50 mg T-HCl oral doses. Systemic availability of the parent substance was 6% and of the active metabolite NT 99%. The terminal half-life of NT was 3.3 h following single oral administration, 4.9 h following intravenous administration and 3.6 h following multiple dosing. Following intravenous infusion, concentrations of unchanged substance were found which were 30 times higher than following oral administration. BNT was eliminated with half-lives of 5 h after oral administration and 6.9 h after intravenous administration. Renal elimination of unchanged substance was 1.6% of the dose following intravenous administration and less than 0.1% of the dose following oral administration. Approximately 3% were recovered in urine as NT and 5% as BNT following both routes of administration.

Tilidine abuse and dependence

Tilidine (Valoron) is a new strong analgesic which was introduced into the market in West Germany in 1970. In February 1978 tilidine was placed under the regulations of the German Narcotics Act because it had rapidly become an easily acquired substitute for opiates on the drug scene. Cases have become known where tilidine dependence developed during the treatment of pain in patients without any preceding addiction to other drugs. The relevant literature on tilidine is reviewed in regard to pharmacological, epidemiological and clinical aspects of tilidine dependence and abuse.

A clinical comparison of tilidine hydrochloride and pentazocine, given orally for the treatment of postoperative pain

A controlled, double-blind study involving 250 women was carried out ot assess the efficacy of oral tilidine 25, 50 and 100 mg in treating postepisiotomy pain, and to offer a comparison with oral pentazocine 50 mg. All the analgesics produced significant pain relief. At peak effect tilidine 50 mg produced very similar results to pentazocine 50 mg with tilidine 25 mg producing less, and tilidine 100 mg more pain relief. These results were not, however, statistically significant. In these postdelivery ambulant patients pentazocine 50 mg and tilidine 100 mg produced at 25% incidence of side-effects, mainly dizziness and drowsiness, but tilidine 25 mg produced significant analgesia with virtually no side-effects.

[Tilidin (Valoron) abuse. Results of an enquiry of drug consumers (author's transl)]

Contrary to previous clinical reports tilidin (Valoron), valuable as a strong analgesic, can replace opiates in young people addicted to them. In the drug scene, therefore, Valoron - very often through irresponsible medical prescription - has become a substitute for opiates. The results of an enquiry about Valoron abuse in 44 opiate addicts are reported. Four cases of isolated Valoron addiction are included which were indistinguishable from the typical career of an opium addict. Further cases of Valoron abuse, estimated at 600, have been mentioned to us, partly by name and partly by number. Doctors and pharmacists are urgently advised to treat Valoron with the same caution prescribed for opiates by the Betäubungsmittelgesetz (= Narcotics Act).

The interaction of tilidine and pethidine in postoperative pain

The mode of interaction between the new, non-narcotic analgesic tilidine and pethidine was studied in the treatment of postoperative pain. The potency ratio 3:1 (pethidine:tilidine) found previously was used in the comparison. Thus 0.25 mg/kg of pethidine with 0.75 mg/kg of tilidine and 0.5 mg/kg of pethidine with 1.5 mg/kg of tilidine were compared with 0.5 mg/kg and with 1.0 mg/kg of pethidine. These drug combinations proved to be equipotent with the pethidine dosages used. Consequently the mode of interaction seemed to be additive synergism. The onset of action was slightly faster with pethidine, but the duration of action was longer with pethidine-tilidine combinations. Respiratory depression and sedation were less evident after pethidine-tilidine combinations than after equianalgesic doses of pethidine. Circulatory effects were similar in all groups. No statistical difference in other side effects could be demonstrated between the groups.