SEARCH · PubMed Health

Results for “Tablets”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 541 records · Page 30Linked to original sources

PubMed2002

Studies of rapidly disintegrating tablets in the oral cavity using co-ground mixtures of mannitol with crospovidone.

We attempted the development of rapid oral disintegration tablets by direct compression using co-ground mixture of D-mannitol and crospovidone. The co-ground mixture was prepared with a vibration rod mill. The tablets were formed by compression using a single punch-tableting machine after addition of the co-ground mixture to non-ground D-mannitol, crospovidone and magnesium stearate. Regarding the properties of tablets, hardness and the time of disintegration were measured. The particle diameter and specific surface area of the co-ground mixture were measured. The tablets manufactured from a physical mixture of 30% (w/w) co-ground mixture of D-mannitol and crospovidone (mixed ratio 9 :1) with 65.5% (w/w) of non-ground mannitol, 4% (w/w) of crospovidone, and 0.5% (w/w) of magnesium stearate had good properties for rapidly disintegrating tablets in the oral cavity. They showed the hardness of 4.9 kg and disintegration time of 33 s. We found that adding co-ground mixture of D-mannitol and crospovidone is useful in enhancing hardness of the tablets that could not be achieved by addition of their individually ground mixture. The improvement in the hardness of the tablets was also observed when other saccharides and disintegrants were used. This method was proved to be applicable in the manufacture of tables of ascorbic acid, a water-soluble drug and nifedipine, a slightly water soluble drug; and the dissolution rate of nifedipine from the tablets in water was remarkably improved. The particle sizes of D-mannitol in the co-ground mixture were smaller than that of the individually ground mixture, resulting in a larger specific surface area of the co-ground mixture than that of the individually ground mixture. Therefore, it was presumed that crospovidone acted as a grinding assistant for D-mannitol in the co-grinding process, enhancing the hardness of tablets by increasing the contact area among powder particles.

Mannitol↗

PubMedDate not supplied

Initial results of the use of prescription order change forms to achieve dose form optimization (consolidation and tablet splitting) of SSRI antidepressants in a state Medicaid program.

BACKGROUND: One method to reduce drug costs is to promote dose form optimization strategies that take advantage of the flat pricing of some drugs, i.e., the same or nearly the same price for a 100 mg tablet and a 50 mg tablet of the same drug. Dose form optimization includes tablet splitting; taking half of a higher-strength tablet; and dose form consolidation, using 1 higher-strength tablet instead of 2 lower-strength tablets. Dose form optimization can reduce the direct cost of therapy by up to 50% while continuing the same daily dose of the same drug molecule. OBJECTIVE: To determine if voluntary prescription change forms for antidepressant drugs could induce dosing changes and reduce the cost of antidepressant therapy in a Medicaid population. METHODS: Specific regimens of 4 selective serotonin reuptake inhibitors (SSRIs)- citalopram, escitalopram, paroxetine, and sertraline- were identified for conversion to half tablets or dose optimization. Change forms, which served as valid prescriptions, were faxed to Oregon prescribers in October 2004. The results from both the returned forms and subsequent drug claims data were evaluated using a segmented linear regression. Citalopram claims were excluded from the cost analysis because the drug became available in generic form in October 2004. RESULTS: A total of 1,582 change forms were sent to 556 unique prescribers; 9.2% of the change forms were for dose consolidation and 90.8% were for tablet splitting. Of the 1,118 change forms (70.7%) that were returned, 956 (60.4% of those sent and 85.5% of those returned) authorized a prescription change to a lower-cost dose regimen. The average drug cost per day declined by 14.2%, from Dollars 2.26 to Dollars 1.94 in the intervention group, versus a 1.6% increase, from Dollars 2.52 to Dollars 2.56, in the group without dose consolidation or tablet splitting of the 3 SSRIs (sertraline, escitalopram, and immediate-release paroxetine). Total drug cost for the 3 SSRIs declined by 35.6%, from Dollars 333,567 to Dollars 214,794, as a result of a 24.8% decline in the total days of SSRI drug therapy and the 14.2% decline in average SSRI drug cost per day. The estimated monthly cost avoidance from this intervention, based on pharmacy claims data, was approximately Dollars 35,285, about 2% of the entire spending on SSRI drugs each month, or about Dollars 0.09 per member per month. Program administration costs, excluding costs incurred by prescribers and pharmacy providers, were about 2% of SSRI drug cost savings. CONCLUSIONS: Voluntary prescription change forms appear to be an effective and well-accepted tool for obtaining dose form optimization through dose form consolidation and tablet splitting, resulting in reduction in the direct costs of SSRI antidepressant drug therapy with minimal additional program administration costs.

Antidepressive Agents, Second-Generation↗

PubMed2005

[Discussion on design and quality control of clinical trials of traditional Chinese medicine on the basis of Fuhuang Tablets clinical study].

OBJECTIVES: To assess the efficacy of Fuhuang Tablets in treating internal hemorrhoid hemorrhage and discussing the design and quality control of clinical trials of traditional Chinese medicine. METHODS: According to two-center, randomized, blinded and controlled study, 144 patients with internal hemorrhoids were divided into 2 groups. Seventy-two patients were treated with Fuhuang Tablets (4 tablets t.i.d. per os) and the other 72 patients were treated with Zhining Tablets (4 tablets t.i.d. per os). Symptoms and signs of the patients were recorded and evaluated at the third and seventh day of treatment respectively. RESULTS: At the third day of treatment, the overall response rates of Fuhuang Tablets-treated group and Zhining Tablets-treated group were 58.57% and 27.78% respectively, with statistic difference between the two groups (P<0.05). At the seventh day of treatment, the overall response rates of Fuhuang Tablets-treated group and Zhining Tablets-treated group were 91.43% and 81.94% respectively, with no statistic difference between the two groups. The laboratory test results and life signs of the 144 patients were normal before and after the treatment. CONCLUSION: Fuhuang Tablets are effective and safe in treating internal hemorrhoid hemorrhage.

Adolescent↗

PubMed2003

Release of indomethacin from bioadhesive tablets containing carbopol 941 modified with Abelmuschus esculentus (okra) gum.

Carbopol 941 (C-941) and Abelmuschus esculentus gum (Okra gum, AEG) were used as bioadhesive polymers in the formulation of mucoadhesive indomethacin tablets. Different batches of the tablet compacts were formulated based on different combination ratios of the polymers. The bioadhesive properties of the tablets were studied using a tensiometer: Tablets coated with 50% w/v solution of Eudragit I. 100 in ethanol, were also prepared and evaluated. The following tablet physical properties were evaluated: hardness, uniformity of weight, disintegration time, friability, and absolute drug content. Release studies were determined in simulated intestinal fluid (SIF pH 7.2) without pancreatin, and in 0.1 N solution of HCl. Result obtained indicated that tablets with equal ratio of C-941 and AEG (1:1) gave the highest bioadhesive strength for both the coated and uncoated tablets. The percentage of drug released ranged from 53-90% for uncoated tablets in 0.1 N HCl and SIF, and 9-16% for coated tablets in 0.1 N HCl, and 63-100% for coated tablets in SIF after 8 hrs.

Abelmoschus↗

PubMed2005

Quality control of tablets by Near Infrared (NIR)-Spectroscopy.

Today, NIR-spectroscopy is an established analytical technique not only in the identification of raw materials but also in the quantification of active ingredients in tablets. In this work calibration models were set up with tablets of the same active ingredient but of miscellaneous origin and manufacturess. Consequently the tablets had different excipients and appearance. The pharmaceutical preparations used included atenolol 100 mg tablets, enalapril 20 mg tablets and acetylsalicylic acid (ASS) tablets of different dosage units. In order to proof if the calibration models set up are generally feasible the assay declared by the manufacturer was used to calculate the partial least square (PLS) calibration. With respect to enalapril tablets simultaneous analysis by HPLC, according to USP 26 was carried out. It was investigated if such methods allow a determination of active ingredients in tablets within limits of +/- 10% of declaration. It was shown that it is possible to set up calibration models to quantify active ingredients in tablets independent of adjuvants or optical appearance. Additionally it could be shown that NIR-spectroscopy is also applicable to determine the concentration of active ingredients in blister-packed tablets.

Atenolol↗

PubMedDate not supplied

[Formulations and bioavailability of propyphenazone in lyophilized tablets].

The present work reports some facts about the preparation and release characteristics of the tablets of propiphenazone made by lyophilizing method (lyoc); they are compared with the classic tablets obtained by simple compression. Our substance, the propiphenazone, is a stable one, but we can talk about its poor solubility. Therefore, in order to obtain the lyoc tablets, we chose the method of paste. This tablets had a spongy aspect, with a desaggregation time of 1-2 min.; the latter (classic tablets) were regularly and the desaggregation time in about 9 min. The kinetics of propiphenazone absorbtion would be expected to differ in these structurally-distinct tablets types. Indeed, the concentration was really appreciable for the lyoc tablets after 30 min., with the peak at 60 min.; for the classic tablets the peak was remarkably only after 90 min. The relative bioavailability for these two types of tablets pointed out the differences, confirming the evident advantages for using the lyoc tablets in analgesic, antipyretic therapy.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed1991

Possible leaching of diethyl phthalate into levothyroxine sodium tablets.

The possible leaching of diethyl phthalate into four currently marketed brands of levothyroxine sodium tablets was investigated. Several strengths of levothyroxine sodium tablets and sizes of containers were used. Samples were analyzed by high-performance liquid chromatography (HPLC) to determine the levothyroxine sodium content and to determine if any unidentified compounds were present. The packaging for the four brands of tablets was also analyzed by using the same HPLC system to determine if any extractable compounds could be detected in the tablets. The potencies of the four brands of tablets were comparable. The tablets from the 100-count container of one brand (brand A) were the only tablets found to contain an unidentified peak in the chromatogram. The desiccants from the bottle showed the same unidentified compound, while the bottle and closure did not yield the peak. Thin-layer chromatography and HPLC identified the peak as diethyl phthalate, a plasticizer in the desiccant. Tablets, bottles, closures, and desiccants for the 1000-count brand A product and all sizes of the other brands were negative for the presence of diethyl phthalate. The desiccants in those containers were from a different manufacturer than the desiccant in the brand A 100-count bottle. Diethyl phthalate in the desiccant in 100-count bottles of brand A levothyroxine sodium tablets appeared to have leached into the tablets.

Drug Contamination↗

PubMed1978

Anthelmintic efficacy of thenium closylate-piperazine phosphate combination tablets against Toxocara canis in pups and young dogs.

Thenium closylate-piperazine phosphate combination tablets, tablets containing either thenium or piperazine, and control tablets (excipients only) were administered in 2 doses 5 to 7.5 hours apart to weaned pups and young dogs, in critical controlled trials to test efficacy against naturally acquired infections of Toxocara canis. In the 1st trial, the combination tablets produced a mean clearance of 94% from 18 pups. Tablets containing thenium alone showed a mean clearance of 9% from 25 pups, and tablets containing piperazine alone caused a mean clearance of 56% from 16 pups. Clearances, corrected for spontaneous worm losses observed in pups treated with the control tablets, were 90% (combination), 5% (thenium alone), and 52% (piperazine alone). In the 2nd and 3rd trials, efficacy of the combination tablet in 15 pups was 78% when corrected for worm losses in pups which had received placebo (excipient) tablets. Each component in the combination tablet contributed its full single-entity efficacy and, if in combination, synergistic effect between the components.

Animals↗

PubMed1995

[Water uptake of tablets, their disintegration and dissolution are in close relation].

Authors investigated the factors influencing this connection on phenylbutazone tablets. Tablets were prepared by wet granulation using three binders (gelatine, hydroxypropyl-cellulose, hydroxyethylcellulose) in different concentrations. Three disintegrants were compared (polyvinylpolypyrrolidon, formalin-casein and cyclodextrin polymer) on the basis of their disintegrating and dissolution-enhancing properties. It was found, that the binder having surface activity improves the wetting of phenylbutazone tablets. Increasing the concentration of gelatine solution, tablets became harder, disintegrated very slowly and the active agent hardly dissolved. Among disintegrants the polyvinyl polypyrrolidon was found to be the best. This material increases the hardness and the drug release as well. The use of cyclodextrin polymer is limited because of the slow water uptake of its tablets. The water uptake of nondisintegrating tablets was described with the Washburn equation. Water penetrates into disintegrating tablets according to the Weibull distribution. The penetration rate can be characterized with the "characteristic water penetration time (t63.2%), obtained from the Weibull equation. The difference between nondisintegrating and disintegrating tablets can be observed in the dissolution kinetic, too. The drug dissolves from the nondisintegrating tablets according to Noyes-Whitney equation (Eq. 1.), from disintegrating tablets according to the modified Noyes-Whitney equation (Eq. 2.) or Weibull equation (Eq. 3.). The dissolution rate constant (K) obtained from the modified Noyes-Whitney equation is proportional with water uptake and in inverse.

Kinetics↗

PubMed1999

Aspirin absorption rates and platelet inhibition times with 325-mg buffered aspirin tablets (chewed or swallowed intact) and with buffered aspirin solution.

Large clinical trials such as the second International Study of Infarct Survival routinely gave patients with myocardial infarction a chewed aspirin, yet there are no data to show whether chewing of aspirin is better, or worse, than swallowing a whole tablet. We performed a randomized, placebo-controlled study to determine whether chewing aspirin or administering it in solution accelerates its absorption and antiplatelet activity. On separate days, 12 fasting volunteers ingested 325 mg of buffered aspirin, either by chewing a tablet for 30 seconds before swallowing it with 4 ounces of water, swallowing a whole tablet with 4 ounces of water, or drinking 4 ounces of Alka Seltzer. Frequent blood samples were obtained for serum aspirin, salicylate, and thromboxane B2 (TxB2) concentrations. With all formulations of aspirin, serum TxB2 decreased 50% when the plasma aspirin concentration reached approximately 1,000 ng/ml. A 50% and 90% decrease in serum TxB2 occurred more quickly after chewing a tablet than after a tablet was swallowed whole. For example, the t 50% for serum TxB2 inhibition was 5.0 +/- 0.6 minutes with the chewed tablet versus 12.0 +/- 2.3 minutes when the tablet was swallowed (p = 0.01). A 50% decrease in serum TxB2 occurred 7.6 +/- 1.2 minutes after Alka Seltzer solution (p = 0.04 vs chewing a tablet; p = 0.13 vs swallowing a whole tablet). Chewing an aspirin tablet is the most effective way of accelerating absorption of aspirin into the blood and shortening the time required for an antiplatelet effect.

Absorption↗

PubMed2000

Development of omeprazole buccal adhesive tablets with stability enhancement in human saliva.

To develop an omeprazole buccal adhesive tablet, the absorption of omeprazole solutions from human oral cavity was evaluated and the physicochemical properties such as the bioadhesive forces of various omeprazole tablet formulations composed of bioadhesive polymers and alkali materials, and the stability of omeprazole tablets in human saliva were investigated. About 23% of the administered dose was absorbed from the oral cavity at 15 min after the administration of omeprazole solutions (1 mg/15 ml). A mixture of sodium alginate and HPMC was selected as the bioadhesive additive for the omeprazole tablet. Omeprazole tablets prepared with bioadhesive polymers alone had the bioadhesive forces suitable for buccal adhesive tablets, but the stability of omeprazole in human saliva was not satisfied. Among alkali materials, only magnesium oxide could be an alkali stabilizer for omeprazole buccal adhesive tablets due to its strong waterproofing effect. Two tablets composed of [omeprazole/sodium alginate/HPMC/magnesium oxide (20/24/6/50, mg/tab)] and [(20/30/0/50, mg/tab)] were suitable for omeprazole buccal adhesive tablets which could be attached to human cheeks without collapse and could be stabilized in human saliva for at least 4 h. It was concluded that these two formulae were potential candidates for the subject of further study for the development of omeprazole buccal adhesive tablets.

Absorption↗

PubMed2000

Application of fibroin in controlled release tablets containing theophylline.

The applicability of fibroin, a major silk protein, to controlled release type dosage tablets was investigated in vitro and in vivo. Fibroin tablets containing theophylline were easily prepared by a direct compression method without additives. Five types of fibroin tablets with the same surface area and different amounts of theophylline were prepared. In an in vitro drug study, the drug release from the tablets was not affected by the pH of the release medium. The greater the fibroin content in the tablets, the lower the percentage released at time t. The Higuchi plots of the release data showed a linear release profile, indicating that the drug release from the fibroin tablets was diffusion-controlled through the matrix. Theophylline powder or a TF-41 tablet (theophylline: fibroin=4 : 1), or a commercial tablet, Uniphyl (once-a-day type) was administered to 5 healthy volunteers. The areas under the saliva theophylline concentration-time curve (AUC) of Uniphyl and TF-41 to that of powder were 85% and 70%, respectively (fasted). Conversely, the mean residence time and mean absorption time of TF-41 were long compared to Uniphyl (fasted). Therefore, the reduction of bioavailability in TF-41 was due to the delayed release from the tablets in vivo. Taken after a meal, the AUCs of TF-41 and Uniphyl increased and the absorption was completed. This suggested that the drug release from TF-41 may increase due to the stimulation of food on TF-41 itself and due to movement of the gastro-intestinal tract. In conclusion, fibroin could be used as the matrix in controlled-release tablets.

Adult↗

PubMed2003

Speed of onset and efficacy of zolmitriptan nasal spray in the acute treatment of migraine: a randomised, double-blind, placebo-controlled, dose-ranging study versus zolmitriptan tablet.

OBJECTIVE: Zolmitriptan oral tablet is highly effective and well tolerated in the acute treatment of migraine with and without aura in adults. A nasal spray formulation has now been developed. The objective of this study was to compare the efficacy and tolerability of fixed doses of zolmitriptan administered via a nasal spray with placebo and zolmitriptan oral tablet in the acute treatment of migraine. PATIENTS AND STUDY DESIGN: This was a randomised, double-blind, double-dummy, placebo-controlled, parallel-group, multicentre, dose-ranging study. 1547 patients aged 18-65 years with an established diagnosis of migraine with or without aura (as defined by International Headache Society criteria) who had at least a 1-year history of migraine and an age of onset <50 years were included. Patients were able to distinguish typical migraine from nonmigraine headaches and had experienced an average of one to six migraine headaches per month during the 2 months preceding the study. Patients were randomised to zolmitriptan (Zomig) The use of tradenames is for product identification purposes only and does not imply endorsement.) nasal spray (5.0, 2.5, 1.0 or 0.5 mg), zolmitriptan oral tablet (2.5mg) or placebo for the treatment of three moderate or severe migraine attacks. The primary outcome measure was headache response at 2 hours following treatment, defined as reduced intensity of migraine pain (using a scale of none, mild, moderate or severe) from severe or moderate at baseline to mild or no pain at 2 hours after treatment. Secondary outcome measures included early headache response at 15, 30 and 45 minutes and headache response at 1 and 4 hours postdose, as well as pain-free rates at 15, 30 and 45 minutes and 1, 2 and 4 hours postdose. Laboratory assessments, vital signs, 12-lead ECGs and nose and throat examinations were performed at screening and follow-up visits. Adverse events were recorded throughout the study using Coding Symbols for Thesaurus of Adverse Reaction Terms (COSTART) terminology. RESULTS: Each dose of zolmitriptan nasal spray produced a greater 2-hour headache response rate than placebo (70.3%, 58.6%, 54.8% and 41.5% for zolmitriptan nasal spray 5.0, 2.5, 1.0 and 0.5mg, compared with 30.6% for placebo [all p < 0.001 vs placebo]). The 2-hour headache response rate for zolmitriptan nasal spray 5.0mg was significantly higher than that of the zolmitriptan 2.5mg oral tablet (61.3%; p < 0.05), while comparisons of nasal spray 0.5, 1.0 and 2.5mg with zolmitriptan 2.5mg oral tablet were not statistically significant. The nasal spray 5.0 and 2.5mg showed a rapid onset of action, with a significant difference in headache response compared with placebo from 15 minutes through 4 hours after administration and a significant difference between the nasal spray 5.0mg and 2.5mg oral tablet from 15 minutes through to 2 hours (the other nasal spray doses were not statistically significant compared with 2.5mg oral tablet). Zolmitriptan nasal spray resulted in pain-free rates that were dose dependent. While all doses from 1.0 mg upwards produced significant pain-free outcomes from 30 minutes versus placebo, only the 5.0mg dose produced pain-free rates significantly superior to both placebo and the 2.5mg oral tablet. Zolmitriptan nasal spray was well tolerated, with the most common adverse events being unusual taste and paresthesia. The majority of adverse events were of short duration and mild or moderate intensity. Only ten patients were withdrawn from the trial because of adverse events. Serious adverse events were reported by nine patients after taking study medication, but none was considered to be causally related to study medication. Zolmitriptan was not associated with any clinically significant changes in laboratory test values or vital signs. CONCLUSION: All doses of zolmitriptan nasal spray produced significant 2-hour headache response rates compared with placebo. The 5.0 and 2.5mg doses were also significantly more effective than placebo for the majority of secondary efficacy measures. Zolmitriptan nasal spray 5.0mg provided a headache response statistically superior to both placebo and the 2.5mg tablet as early as 15 minutes after administration, while demonstrating pain-free outcomes significantly superior to placebo and the 2.5mg tablet as early as 30 minutes after administration. All doses of zolmitriptan nasal spray were well tolerated, resulting in an optimal therapeutic index and clinical recommendation for the 5.0mg dose.

Administration, Intranasal↗

PubMed2006

Formulation of tablets from the crude extract of Rhinacanthus nasutus (Thai local plant) against Aedes aegypti and Culex quinquefasciatus larvae: a preliminary study.

Dried root powder of Rhinacanthus nasutus, Thong Phan Chang (Thai name) were extracted with methanol (MeOH) in a Soxhlet apparatus and made into 2 formulations of tablet containing the extract at 5% and 10% concentration. Due to the viscous and poor flow properties of the crude MeOH extract obtained, a wet granulation method was conducted in developing the tablets. Lactose was used as a filler. Polyvinyl pyrrolidone (PVP) K30 (15% w/w solution in alcohol) was used as the binding agent, while stearic acid (2% w/w) was used as a lubricant. Both formulas of prepared tablets had a smooth shiny surface with a round shape. Other physical properties of the tablets, such as weight variation, friability and disintegration time, met the requirements of the USP XX standard. The mosquito larvicidal activity of prepared tablets containing 5% and 10% R. nasutus extract against Aedes aegypti were not significantly different from each other (p > 0.05), with 48-hour LC50 values of 13.6 and 14.2 mg/I for the 5% and 10% tablets, respectively, while their activities against Culex quinquefasciatus were similar (p > 0.05) with LC50 values of 18.7 and 17.3, respectively. The larvicidal activity levels against Ae. aegypti and Cx. quinquefasciatus were also not significantly different from each other (p > 0.05). No larval mortality was observed in the two control groups: lactose solution and dechlorinated water. Toxicity to female and male fish (Poecilia reticulata) was tested with the prepared tablets. The toxicity of tablets containing 5% and 10% extracts were not significantly different from each other for the P. reticulata females with 48-hour LC50 values of 105.2 and 110.8 mg/I, respectively, and for P. reticulata males with LC50 values of 99.1 and 103.4 mg/I, respectively. Female and male P. reticulata were sensitive to the same dose of the extract. No fish died in the two control groups, with lactose solution and dechlorinated water. Acute-toxicity bioassay with fish showed that with an exposure of 48 hours the LC50 values of the tablets containing 5% and 10% were 5- to 10-fold higher than the LC50 of R. nasutus against mosquito larvae. These prepared tablets could possibly used to control mosquito vectors and be introduced into the mosquito control program.

Acanthaceae↗

PubMed1984

Pharmacokinetics of terbutaline given in slow-release tablets.

Three pharmacokinetic studies of terbutaline slow-release (SR) tablets, 5 and 7.5 mg, were performed in healthy subjects. Four men and 4 women volunteered for each study. Bricanyl plain tablets were used as reference formulation. Both single- and multiple-dose treatments were performed. For repeated administration, SR tablets were given every 12 h. Plain tablets were given every 8 h in two studies and every 12 h in one. Steady-state bioavailability correlated with the amount dissolved in vitro (paddle method) in 6 h. Single-dose bioavailability was limited by the amount dissolved in 4 h. The difference may have a pharmacological explanation, in that repeated administration of a sympathomimetic drug is known to decrease gastro-intestinal motility. Tablets of both strengths with an intermediate dissolution rate were extensively tested. Plasma concentrations and the rates of urinary excretion of unchanged terbutaline were measured. Mean relative bioavailability compared with plain tablets was 76-77% with 7.5 mg SR tablets and 74-80% with those of 5 mg. Variation in bioavailability between and within subjects was the same or smaller with the SR tablets. They gave smoother plasma concentration profiles with delayed peaks and the same peak/trough concentration ratios as the plain tablets, despite less frequent dosing. However, objectively measured side-effects were not significantly reduced. Measurements after cessation of treatment gave terminal half-lives in plasma of 11.5-23.0 h which is considerably longer than reported in the literature. Renal clearance averaged 140 mL/min, similar to predicted creatinine clearance. From these studies it is concluded that the main advantage with the SR tablets is the twice-daily dosage regimen. This should increase compliance, facilitate combination therapy with prolonged-action formulations of other drugs and better maintain therapeutic levels during the whole night interval.

Adult↗

PubMed1979

Relative systemic availability of sulfapyridine from commercial enteric-coated and uncoated sulfasalazine tablets.

The absorption of sulfapyridine after a single 2.0-Gm oral dose of sulfasalazine, the drug of choice in the treatment of inflammatory bowel disease, as commercial uncoated and enteric-coated and uncoated tablets was evaluated in four healthy male adults. The peak plasma concentration of sulfapyridine after the enteric-coated tablets occurred at 20 hours on the average (compared to 14 hours for the uncoated tablets) and was only 50% of that attained from the uncoated tablets (P less than 0.05). The low relative extent of systemic availability of sulfapyridine from the enteric-coated tablets (65.5 +/- 6.3 per cent, mean +/- S.E.) compared to uncoated tablets may be due to absorption rate-dependent presystemic metabolism, since the relative extent of sulfapyridine absorption was 92.7 +/- 6.2 per cent compared to uncoated tablets. These findings suggest that enteric-coated and uncoated tablets of sulfasalazine are not bioequivalent. It remains to be determined whether the clinical efficacy of sulfasalazine from enteric-coated tablets is affected.

Adult↗

PubMed1998

Comparative bioavailability of josamycin, a macrolide antibiotic, from a tablet and solution and the influence of dissolution on in vivo release.

The bioavailability of josamycin from a tablet formulation (2 x Josacine 500 mg tablets) was investigated and compared with the bioavailability of a solution (containing 1 g drug and buffered at pH 4.0) following administration to six healthy human volunteers. Bioavailability profiles for the solution indicated that the drug was inherently rapidly absorbed with a mean Cmax of 1.64 +/- 0.67 mg L-1 attained at a mean tmax of 0.39 +/- 0.08 h. The AUC0-last was 1.510 +/- 0.687 mg h L-1. Bioavailability was significantly lower from the tablets than from the solution. Highly variable serum concentration-time profiles were obtained from the tablets and Cmax values ranged from 0.05 to 0.71 mg L-1 with a tmax range of 0.33-2.0 h. AUC0-last values ranged from 0.03 to 0.95 mg h L-1. Dissolution of josamycin from the tablets was generally unaffected at low pH (pH 1.2-5.0), but, rather, limited predominantly by tablet disintegration. However, dissolution was increasingly limited as the pH increased from 5.0 to 9.0. Besides poor disintegration, the particularly low intrinsic dissolution rate and solubility of josamycin at these pH values is likely to further reduce the dissolution rate. Comparison of the solution and tablet serum concentration-time profiles suggests that the absorption of josamycin from the tablets was dissolution rate limited. This is supported by the in vitro dissolution-pH topogram, which suggests that dissolution will be particularly rate limiting if dissolution of whole or parts of tablets occurs in gastro-intestinal fluid above pH 5.0.

Adult↗

PubMed1998

Bioavailability of morphine after administration of a new bioadhesive buccal tablet.

A new bioadhesive buccal morphine tablet was developed for controlled release delivery of drug and improved bioavailability compared with oral controlled release tablet. In order to characterize the pharmacokinetic properties of this bioadhesive buccal formulation, a bioavailability study was performed in 12 healthy volunteers who received: a 30 mg oral controlled release tablet (A); a 20 mg aqueous solution retained in the mouth for 10 min (B); and the 60 mg bioadhesive buccal tablet placed between the lower gum and lip for 6 h (C). The mean amount of morphine absorbed from the solution was very low, only 2 mg of the 20 mg dose. After administration of forms A and C, plasma levels exhibit typical sustained release concentration-time curves. The mean amount of drug recovered from the residual bioadhesive buccal tablet after 6 h indicated that approximately 50% of the dose was released from the bioadhesive buccal tablet. The relative bioavailability of the buccal tablet (corrected for residual unabsorbed dose) compared with the controlled-release tablet was 98% based on the morphine AUC values. Good correlations between the AUC and the Cmax of the bioadhesive tablet for the drug and metabolite plotted versus the amount of morphine absorbed were found.

Administration, Buccal↗