Ambikeshwar Pratap Singh

Tablet is the most popular dosage form of all existing dosage forms , but in some cases due to the large size of dosage forms, in case of uncooperative, pediatric and dysphasia patients, it may create  problems, to overcome this , a new form of dosage form is developed, which is known as fast dissolving tablets or mouth dissolving tablets. These dosage forms are also used to attain instant higher concentration of drug in body for immediate actions. Gliclazide is an oral antihyperglycemic agent used for the treatment of non-insulin-dependent diabetes mellitus (NIDDM). Fenugreek seed powder was added to this formuation because of  its various pharmacological benefits as well as its self disintegrating property. Mouth dissolving tablets were prepared using direct compression method .Formulations were optimized to develop tablets having minimum possible disintegration time. Tablets were evaluated for hardness, weight variation, friability, wetting time, disintegration time and stability. The main objective of the present research is formulation and evaluation  of mouth dissolving tablets of gliclazide which is an antidiabetic drug ,containing fenugreek seed powder as disintegrating agent.

The colon drug delivery system has gained recent importance in delivery of the drug to the colon. These system facilitate the delivery of the drug to the colon and mainly releases the drug in the colonic environment and thereby reduces various side effects of conventional dosage forms like lower dose is required and hence lowering the side effects caused by higher doses. In the present study natural polysaccharide approach is employed and sesbania gum powder was used as a carrier for delivery of the drug to the colon . Satranidazole was selected as a drug of choice because it is most potent nitroimidazole derivative and clinically useful against common protozoa, it is twice as effective as other nitroimidazoles against amoebiasis. Colon targeted tablet of satranidazole can maintain minimum inhibitory concentration for desired duration in fewer doses with fewer side effects. The aim of the present research work is to develop core tablets of satranidazole and compression coated with different ratios of sesbania gum powder. All the formulations were then subjected for evaluation and were tested for hardness, drug content uniformity an in vitro drug release studies. The compression coated formulation CCS 2 released less than 5% of satranidazole drug in the physiological environment of stomach and intestine, when the dissolution studies was further continued in simulated colonic fluids the compression coated tablets with 150mg of sesbania gum powder released another 70% of satranidazole in the colon after degradation by colonic bacteria at the end of 12 hrs.

Fast dissolving Tablets are disintegrating and/or dissolve rapidly in the saliva without the need for water. Some tablets are designed to dissolve in saliva remarkably fast, within a few seconds, and are true fast-dissolving tablets. Others contain agents to enhance the rate of tablet disintegration in the oral cavity, and are more appropriately termed fast-disintegrating tablets, as they may take up to a minute to completely disintegrate. Oral delivery is currently the gold standard in the pharmaceutical industry where it is regarded as the safest, most convenient and most economical method of drug delivery having the highest patient compliance. By the addition of piperine in the fast dissolving formulation, its bioavailability increases, hence dosing reduces.

By name, colonic drug delivery refers to targeted delivery of drugs into the lower GI tract, which occurs primarily in the large intestine (i.e. colon).Targeted drug delivery to the colon would therefore ensure direct treatment at the disease site, lower dosing and fewer systemic side effects. In addition to the local therapy, the colon also can be utilised as a portal for the drugs into the systemic circulation. Colon targeted drug delivery has gained recent importance for the treatment of colonic diseases and systemic delivery of therapeutic proteins and peptides. Treatment could be more effective if it is possible for drug to be directly delivered to colon. This article gives a detailed information related to colon, various approaches current and novel which are employed for delivery of drugs to the colon and advantages and limitation of colonic drug delivery over conventional drug delivery along with evaluation.