Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Morphine, the principal alkaloid of "papaver somniferum" is the reference substance of central analgesics, the parmacodynamic constants of which are: analgesia and the possibility of addiction. Respiratory depression is, for many of them, a grave side-effect. At the present time, no substance in this category is fully satisfactory and all may result in dependence. Equi-analgesic doses of dextromoramide, phenoperidine and Fentanyl are less than those of morphine, whilst those of pethidine and pentazocine are higher. Study of the pharmacokinetics of these various substances indicates no common elements, and it is difficult to consider that the analgesic action is proportional to blood levels. Clinical assessment of the mean duration of action makes it possible to divide morphine derivatives into substances with a very short action (20 to 45 minutes) such as Febtanyl and phenoperidine, and those with a longer action (1 to 4 hours) which includes the majority of the other substances. The analgesic activity of Methoadone lasts for 4 to 6 hours. Morphine antagonists such as Methadone, nalophine, naloxone and naltrexone possess specific problems in terms of their utilization. Pharmacological data concerning theses substances are described.
 ...
PMID:[Pharmacology of morphine and its derivatives (review)]. 2 28

Samples of heroin-addicted veterans in treatment at a VA drug clinic, ex-addict and nonaddict Vietnam veterans followed-up after return to the United States, and male suicide attempters who were not drug abusers completed a very short (five item) form of the Beck Depression Inventory developed for screening and research purposes. Results confirmed prior findings of high rates of depression among narcotic addicts in treatment. Two samples of patients assessed at intake to treatment did not differ significantly from the suicide patients in BDI-5 scores. Methadone maintenance patients and ex-addicts scored below those groups, but higher than nonaddicts. Relief of inner tensions or worries was chosen most frequently as the reason for continuing use of narcotics by patients in treatment, suggesting that self-medication for psychiatric problems may be common. The BDI-5 proved to be an efficient method for screening for depression in these samples, and thus might be useful in clinical or research settings when a very brief method is needed.
 ...
PMID:Depression in treated narcotic addicts, ex-addicts, nonaddicts, and suicide attempters: validation of a very Brief Depression Scale. 54 68

The respiratory effect of di-methadone administered subcutaneously was examined in awake, unsedated female Labrador retrievers in which a chronic tracheostomy had been established. Respiratory depression was determined from the change in ventilatory response to carbon dioxide. Two methods for assessing the response were evaluated and compared, namely the classical steady-state and rebreathing techniques. Maximal methadone-induced respiratory depression after administration of 2 mg/kg of dl-methadone occurred by 1 hr as detected by both methods, but the magnitude of the response as detected by the steady-state technique was significantly greater. At 8 hr significant respiratory depression was still detectable by the steady-state but not by the rebreathing technique. At comparable serum drug levels, the rebreathing method consistently detected a smaller degree of drug-induced respiratory depression. Methadone administration produced a decrease in slope of the ventilation-response curve which was significant at 1 and 2 hr for both methods. Slopes of the response curves obtained at pretreatment control measurements were markedly different for the two techniques, being significantly greater for the rebreathing method. Serum dl-methadone concentration was measured by radioimmunoassay. The mean serum half-life of methadone was 4.7 hr. There was excellent correlation between the logarithm of serum drug concentration and drug-induced respiratory depression as measured by either technique.
 ...
PMID:Methadone-induced respiratory depression in the dog: comparison of steady-state and rebreathing techniques and correlation with serum drug concentration. 70 33

The respiratory and pupillary effects of oral l-, d-, and d,l-methadone were studied in healthy male volunteers 21 to 35 yr of age. The mean half-life of drug in blood was 22 hr for racemic methadone, 24 hr for l-methadone, and 25 hr for d-methadone. The effects of d-methadone were not significantly different from the placebo response at a 7.5 mg dose, whereas a 50 and 100 mg dose slightly depressed respiration in one subject each. Both 7.5 mg of l-methadone and 15 mg of d,l-methadone induced intense and sustained respiratory depression and miosis. The changes induced by l-methadone were of longer duration than those of d,l-methadone, lasting more than 72 hr in some subjects. Whole blood drug concentration correlated well with respiratory depression and miosis for l- and d,,l-methadone. The potency ratio of l-methadone to d,l-methdone, calculated from blood drug concentration data, was found to be 3.0 for respiratory depression and 2.7 for miosis. The antiduretic effect of 15 mg of d,l-methadone was investigated in three subjects and was found to persist for as long as measurements were taken, namely 11 and 12 hr in two subjects. d,l-Methadone administered frequently for pain may have cumulative effects on respiratory control and ability to excrete a water load.
 ...
PMID:Clinical effects and pharmacokinetics of racemic methadone and its optical isomers. 83 34

We administered the Derogatis Sexual Functioning Inventory to 25 methadone maintenance patients who had been on a stable dose of methadone for at least 2 months, and obtained ratings of depression and anxiety, levels of sex hormones, and liver function tests. Five subjects with significantly lower Global Sexual Satisfaction Index scores (p < .0001) had more psychological symptoms, higher methadone doses, poorer body image, and less sexual drive and satisfaction, but normal fund of sexual information and lifetime experience. Sexual dysfunction among methadone maintenance patients may be due to coexisting psychiatric problems rather than caused by opiates. Methadone patients presenting with sexual dysfunction should receive psychiatric evaluation.
 ...
PMID:Sexual dysfunction and psychological distress in methadone maintenance. 144 65

This double-blind randomised study compared postoperative analgesia after a loading regimen of methadone or morphine in thirty women undergoing abdominal hysterectomy. Methadone or morphine, 0.25 mg.kg-1, was given intravenously at induction of anaesthesia with further increments in the recovery room for analgesia if required. The mean (SD) total doses of methadone and morphine required were 0.43 (0.13) mg.kg-1 and 0.45 (0.15) mg.kg-1 respectively. Patients in the methadone group had lower pain scores in the subsequent 48 hours (P less than 0.001) and required less supplementary intramuscular opioids (P less than 0.001). Ten patients in the methadone group did not request any further opioid analgesics while all patients in the morphine group made at least two requests for opioids. The overall postoperative course was remembered as less painful by patients in the methadone group (P less than 0.001). There was no significant respiratory depression or excessive sedation in either group.
 ...
PMID:A double-blind randomised trial comparing postoperative analgesia after perioperative loading doses of methadone or morphine. 160 41

Methadone maintenance is again receiving attention as an intervention for needle use/sharing among intravenous drug users. A major criticism is that methadone has its own addictive properties; consequently, the client is unable to detoxify and stay off opioids permanently. Study respondents had been off methadone for several years and offered their strategies for success. Motivating forces included the freedom and rewards, such as pride and respect. The following helped individuals to get off and stay off methadone: avoidance of opioids; treatment affiliation to supply ideology and to structure and fill free time; employment; social supports, specifically family and role models; modest plans to avoid disappointment; effective coping skills to avoid depression; and aging and burning out. In addition, those individuals who had immersed themselves in the conventional world, especially those having a higher social class status, had a less difficult time staying off methadone.
 ...
PMID:Staying off methadone maintenance. 161 25

The analgesic and adverse effects of intrathecal methadone 5 mg, 10 mg and 20 mg were assessed and compared with intrathecal morphine 0.5 mg. The study was conducted on 38 patients who underwent total knee or hip replacement surgery. The intrathecal opioid was administered at the end of surgery and assessments began 1 h thereafter and continued for 24 h. Pain measurements, supplementary analgesia requirements, and adverse effects were recorded. Intrathecal morphine 0.5 mg provided effective and prolonged analgesia. Intrathecal methadone 5 mg, 10 mg, and 20 mg produced good analgesia of 4 h duration. Thereafter the median pain scores with intrathecal methadone were consistently higher (worse) than those with intrathecal morphine (P less than 0.05). The time to the onset of discomfort severe enough to require supplemental morphine was longer after intrathecal morphine than following methadone (15 h with morphine 0.5 mg; 6.25 h, 6.5 h and 6 h with methadone 5 mg, 10 mg, and 20 mg respectively: P less than 0.05). Central nervous system depression manifesting as respiratory depression, hypotension, and excessive drowsiness occurred in 3 of 8 patients injected with methadone 20 mg intrathecally. Generalized pruritus, nausea, vomiting, and urinary retention were common and equally distributed among the treatment groups. We conclude that both intrathecal morphine 0.5 mg and methadone 5, 10, and 20 mg provide excellent analgesia but that morphine has a more prolonged effect. Methadone 20 mg produced unacceptable side effects. Clinical evidence for rostral spread of methadone within the CSF, as indicated by facial itching and excessive drowsiness, was less apparent with 5 mg than with 10 and 20 mg. Various explanations for the observed differences between the drugs are discussed.
 ...
PMID:Intrathecal methadone: a dose-response study and comparison with intrathecal morphine 0.5 mg. 208 26

Methadone is described in this review as a potent analgesic agent; in Germany it is seldom administered as a therapeutic agent. It has the following pharmacokinetic properties: high lipophilicity, large volume of distribution (initial and steady state), low clearance (hepatic capacity limited) with a long terminal elimination time, high bioavailability following oral administration, and a tendency to accumulate in the blood and tissues. The review also considers pharmacodynamic aspects of methadone, which in Germany is available only in the levo-rotatory form; all the effects are conditioned by this l-enantiomer. In other countries methadone is successfully used over the following range of indications: intra- and postoperative pain (intravenous and epidural administration), cancer pain, and non-malignant painful conditions. The concepts of minimal effective analgesic concentration in the blood plasma (MEAC) and concentration required for 50% relief on pain are discussed. The MEAC is lower for the l-isomer than for the racemate. Methadone alone is a good analgesic agent that has slight effects in the form of respiratory depression, to which partial tolerance builds up in the course of long-term use of the drug. The interaction between methadone with alcohol, benzodiazepines, and barbiturates can be dangerous.
 ...
PMID:[Methadone--pharmacokinetics and pharmacodynamics of an opiate]. 256 28

A double-blind study of patients selected at random compared the analgesic and adverse effects of intrathecal methadone (1 mg) with those of intrathecal morphine (0.5 and 1 mg). The study was conducted on 30 patients who underwent major orthopedic or urologic surgery. The intrathecal opioid was administered at the end of surgery, and assessments began 1 h thereafter and continued for 20 h. Pain measurements, supplementary analgesia requirements, and adverse effects were recorded. Intrathecal morphine (0.5 and 1 mg) provided effective and prolonged analgesia. Methadone, however, was unable to ensure the same degree of analgesia; consequently, the median pain scores were consistently higher following methadone than morphine (0.5 and 1 mg) (P less than 0.05). The time to the onset of discomfort severe enough to require supplemental morphine was longer after intrathecal morphine than that following methadone (24 and 29 h with morphine 0.5 and 1 mg; 6.5 h with methadone; P less than 0.05). Respiratory depression (increases PaCO2) was not associated with methadone and morphine 0.5 mg but was common following morphine 1 mg (P less than 0.05). Facial pruritus was unique to intrathecal morphine. Urinary retention requiring bladder catheterization was more frequent following morphine than methadone, although this was not statistically significant. Nausea and vomiting were common to all groups. Intrathecal morphine (0.5 and 1 mg) provides superior postoperative analgesia to 1 mg methadone. Various explanations for the observed differences between the drugs are discussed, including the possibility that the dose of methadone used in the subarachnoid space was inadequate and that a larger dose might have produced an effect equal to that of morphine.
 ...
PMID:Intrathecal methadone and morphine for postoperative analgesia: a comparison of the efficacy, duration, and side effects. 235 28


1 2 3 4 5 6 Next >>