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[Influence of ethanol on the in vitro and in vivo drug release from some sustained release tablets (author's transl)].

The in vitro and in vivo liberation of acetylsalicylic acid from sustained release tablets in presence of ethanol is described. Simultaneous uptake of 120 ml commercial brandy resulted in a faster release of the active substance from the tablets prepared with Eudragit ret-l (PM), as has been proved by urinary excretion data. These results were supported by experiments with a pH-endoaradio transmitter and by radiography.

Adult

Effect of formulation of intramuscular injections of phenothiazines on duration of activity.

Trifluoperazine and pericyazine were formulated using both the hydrochloride and embonate salts, and some comparisons were made with the activity of fluphenazine salt and ester formulations. Simple solutions in polyethylene glycol, gelled aqueous solutions, nonaqueous suspensions, multiple emulsions, and microencapsulated preparations were formulated, and their duration of activity was tested in dogs. While the multiple emulsion system showed some promise, a nylon microcapsule system produced significant prolonged activity of the drug after deep intramuscular injection.

Animals

Effect of topically applied pilocarpine on tear film pH.

Changes in tear film pH were observed during the 1st hr after instillation of pilocarpine in various dosage forms to the rabbit eye. In anesthetized rabbits, with periodic blinking induced electrically, commercial formulations of pilocarpine salts applied as drops or a spray acutely lowered tear film pH by 1.1-1.6 pH units. The pH remained below pretreatment levels for 45-greater than 60 min after instillation. Pilocarpine base, administered continuously at the rates of 20 or 80 mug/hr from ocular therapeutic systems, had little or no effect on tear film pH in this same animal preparation. The reduction in tear film pH produced by pilocarpine eyedrops or spray solution is attributable to the acid pH and buffer capacity of these solutions. Delivery of pilocarpine base without pH change was achieved with ocular therapeutic systems, because the drug (pKa = 7.07) was delivered free, or virtually so, of excipients. These observed differences in tear film pH after application may partially explain the four- to eightfold reduction in total effective pilocarpine dose with ocular therapeutic systems compared to eyedrops or spray, since the cornea is less permeable to ionized than to unionized molecules.

Administration, Topical

Comparative Bioavailability of Trimodal (CTx-1301) Versus Bimodal Dexmethylphenidate Modified-Release Formulations in Adults with Attention-Deficit/Hyperactivity Disorder: A Randomized, Single-Dose, Crossover Study.

BACKGROUND AND OBJECTIVES: Attention-deficit/hyperactivity disorder (ADHD) is a chronic neurodevelopmental disorder that often requires sustained symptom control throughout the day. Although bimodal extended-release dexmethylphenidate (d-MPH XR) formulations provide initial and intermediate drug release, they may not consistently maintain therapeutic exposure into the late afternoon and evening. Trimodal formulations with an additional delayed release component may extend drug exposure later in the day, although this remains to be established. To explore differences in pharmacokinetic (PK) profiles between trimodal (CTx-1301) and bimodal delivery of d-MPH XR, a comparative bioavailability study was conducted at the highest and lowest doses for both formulations. METHODS: In this randomized, 4-period, crossover study, adults with ADHD received single doses of CTx-1301 (50 mg and 6.25 mg) and d-MPH XR (40 mg and 5 mg). Comparative bioavailability was assessed through adjusted geometric mean ratios for exposure parameters (maximum observed plasma concentration [Cmax], area under plasma concentration-time curve to last measurable concentration [AUClast] and extrapolated to infinity [AUC0-inf]), with a prespecified bioequivalence range of 0.80 to 1.25. Secondary endpoints included partial AUCs and safety assessments. RESULTS: The study population (N = 45) was predominantly male (88.9%) and White (55.6%), with mean age of 29.6 ± 8.01 years. Adjusted geometric mean ratios comparing the primary exposure parameters (Cmax, AUClast, and AUC0-inf) for CTx-1301 versus d-MPH XR were within the bioequivalence range (0.80-1.25) at both the high and low doses. The CTx-1301-to-d-MPH XR partial AUC ratios were within the bioequivalence range from 0 to 9 hours post-dose. At later intervals (AUC9-12 and AUC12-16), adjusted geometric mean ratios exceeded the upper bioequivalence threshold, consistent with the expected contribution of the third medication release component. Dose proportionality was observed between the two CTx-1301 doses and two d-MPH XR formulations. CTx-1301 was generally well tolerated. The most commonly reported adverse events included tachycardia, insomnia, headache, nausea, and euphoric mood. The incidence of treatment-emergent adverse events was numerically lower with CTx-1301 than with d-MPH XR; however, no statistical analysis was performed. CONCLUSIONS: Key exposure parameters including Cmax, AUClast, and AUC0-inf for trimodal CTx-1301 were statistically bioequivalent to bimodal d-MPH XR. Interval‑specific PK analyses demonstrated higher exposure with CTx‑1301 during later post-dose intervals (9-16 h), consistent with the formulation's third release component. However, the clinical relevance of these PK differences requires further evaluation. CTx-1301 demonstrated dose proportionality and was well tolerated at high and low doses. REGISTRATION: ClinicalTrials.gov, NCT04138498; 19 September 2019.

Humans

Characterization of local tolerability of TV-46000, a long-acting subcutaneous formulation of risperidone for the treatment of schizophrenia.

TV-46000 is a long-acting injectable antipsychotic (LAI) approved for the treatment of adults with schizophrenia and bipolar I disorder. LAIs like TV-46000 can improve adherence and reduce relapse in patients with schizophrenia; however, injection site reactions (ISRs) can contribute to LAI discontinuation. ISRs with TV-46000 treatment were characterized using data from two phase 3 trials of patients with schizophrenia (RISE [NCT03503318], SHINE [NCT03893825]) and a phase 1 study of patients with schizophrenia or schizoaffective disorder. Patients in the pooled safety population (aged 16-67 years) from RISE and SHINE (n = 525 TV-46000, n = 179 placebo) received 4554 TV-46000 injections and 2721 placebo injections. ISRs were reported in 19 % (n = 102) of patients who received TV-46000, corresponding to an exposure-adjusted event rate (EAER)/100 patient-years of 48.67. ISRs led to 9 (1.7 %) treatment discontinuations of TV-46000. The most frequently reported ISR adverse events were injection site pain (EAER, 15.38, n = 36 [7 %]) and injection site nodule (EAER, 12.01, n = 35 [7 %]). ISR frequency and pain and nodule adverse event frequency decreased after the first injection. In the phase 1 study (n = 99), mean injection site pain scores were highest immediately after injection, showed a notable decrease within 10 min of injection, and further decreased within 1 h after injection. In conclusion, for >4500 injections evaluated, ISR rates with TV-46000 were modest. Most ISRs were mild or moderate and rarely led to treatment discontinuation. Results support the favorable tolerability of TV-46000 as a treatment for schizophrenia in adults.

Humans

Weight and metabolic changes in patients with schizophrenia treated with paliperidone palmitate 6-month formulation versus paliperidone palmitate 3-month formulation: a post-hoc analysis.

OBJECTIVE: To determine the effect that paliperidone palmitate 6-month long-acting injectable formulation (PP6M) had on metabolic parameters including body weight (BW), and blood lipid profiles, a post-hoc analysis was conducted to assess changes in BW from baseline to the end of study based on age, body mass index (BMI), and changes in blood lipid profiles during a 12-month, phase 3, double-blind (DB) clinical study. Long term effects of PP6M on BW and BMI were further explored during a 24-month extension study in which participants were treated exclusively with PP6M. METHOD: In the 12-month DB phase, participants were randomized to receive PP6M or paliperidone palmitate 3-month long-acting injectable formulation (PP3M). The mean change in BW and abnormal weight percent change from baseline were calculated at endpoint by age, gender, and BMI. Additionally, treatment-emergent shifts from baseline for the four key lipid parameters (fasting low density lipoprotein [LDL], fasting triglycerides [TG], fasting total cholesterol [TC], and fasting high density lipoprotein [HDL]) during DB were assessed. Following this study, participants were given the opportunity to transition to a 24-month extension study and be treated with PP6M. The mean change and percent change in BW, and the mean change in BMI from DB baseline to the end of the extension study (36&#xa0;months total) were calculated. RESULTS: Participants who were treated with PP6M showed numerically less weight gain, BMI, waist circumference, and more weight decrease compared to PP3M group during 12-month DB phase, though the proportion of participants reporting an abnormal change (&#x2265;7% change) in BW did not significantly differ between PP3M and PP6M. The weight differences were more pronounced in the younger age group (18-25&#xa0;years) and those who were overweight (BMI: 25 to <30&#xa0;kg/m2. Numerical differences in favor of PP6M were found in fasting blood lipids (HDL, LDL, TG, and TC). The changes in BW and BMI over time remained consistent throughout the 24-month extension, favoring PP6M in each instance. CONCLUSIONS: This post-hoc analysis demonstrated that PP6M was comparable to PP3M in terms of metabolic parameters; however, it may have a beneficial effect on weight gain, especially in young patients. TRIAL REGISTRATION: Post-Hoc Analysis of Studies NCT03345342 and NCT04072575 (ClinicalTrials.gov). Significant outcomes The findings from this study have highlighted that participants who were treated with the 6-month long-acting injectable formulation of paliperidone exhibited less weight gain during treatment overall, and significantly less weight gain in adolescents and young adults. Importantly, this trend continued over the course of long-term treatment, regardless of age. Participants treated with the 6-month formulation also had fewer shifts in blood lipids outside of the normal range and had more favorable changes in body mass index and waist circumference. These results suggest that when considering metabolic dysregulation as a factor in choosing a long-acting injectable antipsychotic, the 6-month formulation is a viable alternative to the 3-month formulation, particularly in younger patients with schizophrenia. Limitations Because this is a post hoc analysis and the study was not powered to test weight and metabolic changes, most endpoints were summarized descriptively and the statistical test was limited to the main endpoint (abnormal percent weight gain and loss).

Adult

The expectation of outcome from maintenance therapy in chronic schizophrenic patients.

The results from a prospective follow-up study of a group of schizophrenic patients suggest that a significant proportion (41 per cent) are likely to relapse during a two-year period despite the prescription of long-acting injectable neuroleptic drugs. Some will relapse because of a failure of the regime, but others (32-37 per cent) because the pharmacological protection of these drugs would appear to be less effective in certain patients. Even with the major advantages of the long-acting injectable neuroleptics over oral medication, the schizophrenic patient population remains a group with a high incidence of psychiatric and social morbidity which continues to require the full resources of both the hospital and community services.

Brief Psychiatric Rating Scale

Aspirin-induced gastritis and gastrointestinal bleeding.

Aspirin-induced gastritis and gastrointestinal hemorrhage were reviewed and discussed on the basis of currently available literature. Acute hemorrhagic gastritis occurs in from 50% to 70% of all patients taking aspirin, is not directly related to dose size, and can be severe enough to cause death in a few cases. No tolerance appears to ever develop. The mechanism that causes this bleeding is not definite, but the back diffusion of H+ ions accross the gastric barrier seems to bear primary responsibility, with physical erosion, prolonged platelet bleeding, and the effect of low pH values also being possible explanations. There appears to be less acid present in the stomach when bleeding occurs, but this is a masking effect of the aspirin that causes increased absorption of the H+ ions. Factors important in determining pharmaceutical formulation are method of administration, particle size of the aspirin, duration of contact between the drug and the mucosa, presence of buffers in the drug to raise the gastric pH, dissolution rate of the drug in the stomach, and ionization characteristics of the drug itself. Gastrointestinal blood loss caused by aspirin can be minimized by administering the drug in one of these forms:--a dilute solution of acetylsalicylate;--an intravenously injected solution;--a very rapidly dissolving and rapidly absorbed tablet;--a solution with sufficiently large amounts of antacid added;--a fine-grain, highly buffered aspirin tablet;--an enteric-coated tablet that does not dissolve in the stomach; or--an aspirin substitute such as acetaminophen.

Administration, Oral

Critical study of the use of long acting neuroleptics (depot neuroleptics) in France.

Long acting neuroleptics (L.A.N.) represent 11% of the medical prescription of neuroleptics in France (about 40,000 patients in 1974). Some psychiatrists remain reluctant to prescribe long acting-neuroleptics and many problems related to their use are still solved empirically:1) relation between the posology of the standard Neuroleptic and the corresponding L.A.N. 2)the problem of dose-interval. 3) the necessary prescription of an parkinsonian. The superiority of N.A.P. over the Neuroleptic Standard has received no experimental confirmation in France, but the L.A.N. appear to us as an original therapy, the "pivot chemotherapy" around which psychotherapy and sociotherapy can be arranged without anarchical and ceaseless changes of neuroleptic compounds and of posology.

Antipsychotic Agents

[Zollinger-Ellison syndrome treated medically by an inhibitor of H2 histamine receptors].

Metiamide an histamine H2-receptors antagonist has been used to treat a case of Zollinger-Ellison syndrome characterized by a long standing diarrhea, an important gastric hypersecretion and a moderatly elevated plasma gastrin but without digestive ulceration. At the dose of 600 mg per day, Metiamide induced a complete suppression of acid secretion, an effect which lasted for 15 days after stopping the drug. Accordingly and since the only finding at time of laparotomy was a small lymph node enlarged with endocrine metastatic tissue, the stomach was left intact and Metiamide pursued. During the first 4 months of chronic administration of Metiamide, acid secretion was maintained at levels below 25 p.cent of initial values. Ulteriorly however, although dosages of Metiamide were increased, acid hypersecretion resumed and a duodenal ulcer developed. Total gastrectomy was then performed 11 months after the beginning of Metiamide. In spite of the failure of Metiamide treatment, the long term follow up of this case of Zollinger-Ellison Syndrome, allowed us to get theoretical and practical informations.

Adult

[Drug-drug interactions (author's transl)].

This short outline of drug-drug interactions does not claim to cover the entire field. The task of this paper is to illustrate the most important principles of drug-drug interactions by paradigms taken from the experience of the practitioner. One consequence of drug-drug interactions is the change in pharmacolinetic parameters important for the therapeutical effect of drugs in the organism. Very often the elucidation of the mechanisms of drug-drug interactions in man is impossible; therefore, for clinical pharmacologists experiments on animals remain the tool in order to gain more knowledge in this field.

Age Factors

[Galenical possibilities and problems in protraction of drug effects (author's transl)].

In recent years, dosage forms with sustained release have obtained a significant importance. The technological possibilities for manufacturing are described as coating, embedding and matrix procedures. The range of auxiliary substances, which are responsible for the retardation of drug activity, reaches from lipophilic compounds as lipoids, fatty alcohols and compounds which are forming hydrogels as cellulose derivatives and natural polysaccharides to synthetic polymers derived from acrylic acid. The formulation of the dosage forms requires particular care in respect to the amount of initial and maintenance doses. On account of technological processes, for example during manufacturing of tablets, under certain circumstances the liberation rate is altered. In vitro test methods allow comparisons only then when the results can be counter-checked by in vitro experiments. The release of drug follows different mechanisms, which are described, entirely or in part, to be reactions following the time law of zero or first order. In special cases, a linear correlation is observed as a function of square root of time. The calculation of given special equations for events within the dosage form is feasible from blood-level values.

Biological Availability

[The influence of neuroleptic drugs on urinary excretion of non-protein nitrogen (author's transl)].

During treatment with thioxanthenes or phenothiazines of schizophrenic patients non-protein nitrogen in urine was measured. The values were calculated in relation to the excretion of creatinine. a) Flupentixol or fluphenazine applied in optimal dosage, increased the excretion of urea and the amino acids asp, glu + gln, and gly. b) Moreover, if the drug induced a parkinsonoid (thioridazine) the excretion of ser and thr was increased, too. The usual desalting procedure by ion-exchanging resins before chromatography increases the contents of several amino acids, e.g. asp, asn, ala, gly, cys, ser, thr, indicating a breakdown of some instable products.

Amino Acids