In vivo bioavailability studies of sumatriptan succinate buccal tablets

Back ground and the purpose of study

Sumatriptan succinate is a Serotonin 5- HT1 receptor agonist, used in treatment of migraine. It is absorbed rapidly but incompletely when given orally and undergoes first-pass metabolism, resulting in a low absolute bioavailability of about 15%. The aim of this work was to design mucoadhesive bilayered buccal tablets of sumatriptan succinate to improve its bioavailability.

Methods

Mucoadhesive polymers carbopol 934 (Carbopol), HPMC K4M, HPMC K15M along with ethyl cellulose as an impermeable backing layer were used for the preparation of mucoadhesive bilayered tablets. In vivo bioavailability studies was also conducted in rabbits for optimized formulation using oral solution of sumatriptan succinate as standard.

Results

Bilayered buccal tablets (BBT) containing the mixture of Carbopol and HPMC K4M in the ratio 1:1 (T1) had the maximum percentage of in vitro drug release within 6 hrs. The optimized formulation (T1) followed non-Fickian release mechanism. The percentage relative bioavailability of sumatriptan succinate from selected bilayered buccal tablets (T1) was found to be 140.78%.

Conclusions

Bilayered buccal tablets of sumatriptan succinate was successfully prepared with improved bioavailability.     

Unilateral tremor induced by risperidone in a patient with acute mania: vitamin B12 deficiency as possible mediating factor

Identification and management of drug-induced movement disorders is a clinical challenge, more so when the clinical presentation is atypical. A young male with acute mania was under treatment with sodium valproate and risperidone. He developed tremors of right hand and neck. These were present at rest and exacerbated by mental activity, when under observation and during voluntarily initiated activity. There were no associated extra pyramidal symptoms or cerebellar signs. Investigations for other common causes of tremors did not reveal any evidence except for low value of serum vitamin B12 levels. The tremors persisted after the withdrawal of valproate, but resolved following the withdrawal of risperidone. It is a common dictum that drug-induced tremors are bilateral. This may not be true always as we found out in our case. These movements were probably induced by risperidone. This atypical presentation could be due to concurrent use of valproate and low serum vitamin B12 levels.     

Preoperative embolization of primary bone tumors:A case control study

AIM:To study the safety and effectiveness of preoperative embolization of primary bone tumors in relation to intraoperative blood loss,intraoperative blood transfusion volume and surgical time.METHODS:Thirty-three patients underwent preoperative embolization of primary tumors of extremities,hip or vertebrae before resection and stabilization.The primary osseous tumors included giant cell tumors,aneurysmal bone cyst,osteoblastoma,chondroblastoma and chondrosarcoma.Twenty-six patients were included for the statistical analysis(embolization group)as they were operated within 0-48 h within preoperative embolization.A control group(non-embolization group,n = 28)with bone tumor having similar histological diagnosis and operated without embolization was retrieved from hospital record for statistical comparison.RESULTS:The mean intraoperative blood loss was 1300 mL(250-2900 mL),the mean intraoperative blood transfusion was 700 m L(0-1400 m L)and the mean surgical time was 221 ± 76.7 min for embolization group(group Ⅰ,n = 26).Non-embolization group(group Ⅱ,n = 28),the mean intraoperative blood loss was 1800 m L(800-6000 m L),the mean intraoperative blood transfusion was 1400 mL(700-8400 mL)and the meansurgical time was 250 ± 69.7 min.On comparison,statistically significant(P < 0.001)difference was found between embolisation group and non-embolisation group for the amount of blood loss and requirement of blood transfusion.There was no statistical difference between the two groups for the surgical time.No patients developed any angiography or embolization related complications.CONCLUSION:Preoperative embolization of bone tumors is a safe and effective adjunct to the surgical management of primary bone tumors that leads to reduction in intraoperative blood loss and blood transfusion volume.     

Is maternal anxiety a barrier to exclusive breastfeeding?

Objective: To assess the association of maternal anxiety with nonadherence to exclusive breastfeeding.

Methods: This questionnaire-based study was conducted at a tertiary care teaching hospital in South India mothers with infants less than 6 months of age and not exclusively breastfeeding were interviewed and their demographic and clinical details were noted. The Iowa Infant Feeding Attitude Scale (IIFAS) and Hospital Anxiety and Depression Scale (HADS) were administered to these mothers.

Results: A total of 85 mother–infant dyads were included. The mean age of the mothers was 26 years and 57% were from urban areas. Among the additional feeds given, cow’s milk was the commonest (57.6%), followed by gripe water (28.2%) and formula feeds (16.5%). The mean HADS anxiety subscale score was 12.2 (±5.3) and HADS depression subscale score was 9.5 (±3.8). The mean score on IIFAS was 58.4 (±3.6) suggesting a relatively favorable attitude toward breastfeeding. On linear regression analysis, higher HADS depression score, lower birth weight and lower per capita income were independent predictors of poorer attitudes toward breastfeeding.

Conclusion: Maternal anxiety may be an independent risk factor for nonadherence to exclusive breastfeeding for the initial six months.     

Isolated Ventricular Septal Rupture Caused by Non-Penetrating Trauma to the Chest

Cardiac injury following blunt trauma is an important cause of morbidity and mortality and is often unsuspected. Isolated chamber rupture and valvular injury are infrequent but recognized consequences of non-penetrating trauma. The diagnosis is generally based on clinical and ECG findings and is further confirmed on echocardiography. This report describes imaging findings of isolated ventricular septal rupture as seen on MDCT.