IMMEDIATE RELEASE DRUG DELIVERY SYSTEM (TABLETS)

IMMEDIATE RELEASE DRUG DELIVERY SYSTEM (TABLETS)

Rishikesh*, Mohiuddin Ahmed Bhuyian, Irin Dewan, Drishti Rani Ghosh & Md. Asraful Islam

Department of Pharmacy, University of Asia Pacific, Dhaka-1209, Bangladesh

ABSTRACT

Tablet is the most popular among all dosage forms existing today because of its convenience of self-administration, compactness and easy manufacturing; however in many cases immediate onset of action is required than conventional therapy. There are novel types of dosage forms that act very quickly after administration. The basic approach used in development tablets is the use of superdisintegrants like Cross linked carboxymelhylcellulose (Crosscarmellose), Sodium starch glycolate (Primogel), Kollidon Cl etc. which provide instant disintegration of tablet after administration. A new dosage form allows a manufacturer to extend market exclusivity, while offering its patient population a more convenient dosage form or dosing regimen. In this regard, immediate release formulations are similar to many sustained release formulations that are now commonly available.

Immediate release, Superdisintegrants. Direct compression, Wet Granulation

INTRODUCTION: Oral administration is the most popular route for systemic effects due to its ease of ingestion, pain, avoidance, versatility and most importantly, patient compliance. Also solid oral delivery systems do not require sterile conditions and are therefore, less expensive to manufacture. Patient compliance, high-precision dosing, and manufacturing efficiency make tablets the solid dosage form of choice. Excipients and equipments choices will be significantly affected should solid dosage form technologies change in response to the unprecedented shifts in the drug discovery such as genomics. Injections generally are not favoured for use by patients unless facilitated by sophisticated auto injectors. Inhalation is one good alternative system to deliver these drugs, but the increased research into biopharmaceuticals so far has generate predominantly chemical entities with low molecular weights.

The development of enhanced oral protein delivery technology by immediate release tablets which may release the drugs at an enhanced rate are very promising for the delivery of poorly soluble drugs high molecular weight protein and peptide . The oral route remains the perfect route for the administration of therapeutic agents because the low cost of therapy, manufacturing and ease of administration lead to high levels of patient compliance ^{1, 2, 3, 4, 5, 6, 7, 8}.

Many patients require quick onset of action in particular therapeutic condition and consequently immediate release of medicament is required. It is estimated that 50% of the population is affected by this problem, which results in a high incidence of ineffective therapy ^{9, 10}. The term “immediate release” pharmaceutical formulation includes any formulation in which the rate of release of drug from the formulation and/or the absorption of drug, is neither appreciably, nor intentionally, retarded by galenic manipulations.

In the present case, immediate release may be provided for by way of an appropriate pharmaceutically acceptable diluent or carrier, which diluent or carrier does not prolong, to an appreciable extent, the rate of drug release and/or absorption.

Thus, the term excludes formulations which are adapted to provide for “modified”, “controlled”, “sustained”, “prolonged”, “extended” or “delayed” release of drug ^{11, 12, 13}.

Difficulties ^{5, 8}:

• Patient may suffer from tremors therefore, they have difficulty to take tablet, powder and liquids. In dysphasia physical obstacles and adherence to an oesophagus may cause gastrointestinal ulceration.
• Swallowing of solid dosage forms like tablet and capsules and produce difficulty for young adult of incomplete development of muscular and nervous system and elderly patients suffer from dysphasia.

Criteria for Immediate Release Drug Delivery System ^{7, 8}: Immediate release dosage form should-

• In the case of solid dosage it should dissolve or disintegrate in the stomach within a short period.
• In the case of liquid dosage form it should be compatible with taste masking.
• Be portable without fragility concern.
• Have a pleasing mouth feel.
• It should not leave minimal or no residue in the mouth after oral administration.
• Exhibit low sensivity to environmental condition as humidity and temperature.
• Be manufactured using conventional processing and packaging equipment at low cost.
• Rapid dissolution and absorption of drug, which may produce rapid onset of action.

Candidate for Immediate Release Oral Dosage Form:

1. Analgesics and Anti-inflammatory Agents: Aloxiprin, auranofin,azapropazone, benorylate, diflunisal, etodolac, fenbufen, fenoprofen calcim, flurbiprofen, ibuprofen, indomethacin, ketoprofen, meclofenamic acid, mefenamicacid, nabumetone, naproxen, oxaprozin, oxyphenbutazone, henylbutazone, piroxicam, sulindac.
2. Anthelmintics: Albendazole, bephenium, hydroxynaphthoate, cambendazole, dichlorophen, ivermectin, mebendazole, oxamniquine, oxfendazole, oxantel embonate, praziquantel, pyrantel embonate, thiabendazole.
3. Anti-Arrhythmic Agents: Amiodarone HCl, Disopyramide, flecainide acetate,quinidine sulphate.
4. Anti-bacterial Agents: Benethamine penicillin, cinoxacin, ciprofloxacin HCl, clarithromycin, clofazimine, cloxacillin, demeclocycline, doxycycline, erythromycin, ethionamide, Imipenem, nalidixic acid, nitrofurantoin, rifampicin, spiramycin, sulphabenzamide, sulphadoxine, sulphamerazine, sulphacetamide, sulphadiazine, sulphafurazole, sulphamethoxazole, sulphapyridine, tetracycline, trimethoprim.
5. Anti-coagulants: Dicoumarol, dipyridamole, nicoumalone, phenindione.
6. Anti-depressants: Amoxapine, ciclazindol, maprotiline HCl, mianserin HCl, nortriptyline HCl, trazodone HCl, trimipramine maleate