What is the use of dosage forms?

Answer 1

The vast majority of drug substances are administered in milligram quantities, much too small to be weighed easily.

When the dose of a drug is minute, as that of ethinyl estradiol (0.5mg) solid dosage forms such as tablets and capsules must be prepared with fillers or diluents so that the size of resultant dosage unit is large enough to pick up with the finger tips.

Basic Reasons for Designing a Dosage Form

Besides providing the mechanism for safe and convenient delivery of accurate dosage, dosage forms are needed for additional reasons.

1. PROTECTION OF DRUG FROM EXTERNAL FACTORS

For the protection of drug substance from the destructive influences of atmospheric oxygen or humidity for example coated tablets, sealed ampoules,

2. PROTECTION OF DRUG FROM GASTRIC ACID

For the protection of a drug substance from the destructive influence of gastric acid after oral administration for example enteric coated tablets.

3. MASKING TASTE OR ODOUR

To conceal the bitter salty or offensive taste or odour of a drug substance.

(e.g. capsules flavored syrups)

4. PROVIDING A SUITABLE MEDIUM

To provide a suitable vehicle or medium for the preparations of substances that are either insoluble or unstable elsewhere.

(e.g. suspension dosage form)

5. CONTROLLED DRUG ACTION

To provide time, to control drug action.

(e.g. various controlled release tablets, capsules and suspensions)

6. FOR TOPICAL DRUG APPLICATION

To provide optimal drug action from topical administration sites.

(e.g. ointments, creams, transdermal patches and nasal preparations)

7. FOR DRUG ADMINISTRATION IN BODY ORIFICES

To provide for the insertion of the drug into one of the body orifices

(e.g. rectal and vaginal suppositories)

8. FOR DIRECT ADMINISTRATION INTO BLOOD

To provide for the placement of drugs directly into the blood stream or into body tissues.

(e.g. injections)

9. TO ADMINISTER DRUG INTO NASAL PASSAGE AND RESPIRATORY TRACT

To provide for optimal drug action through inhalation therapy.

(e.g. inhalants and inhalation aerosols)

10. FOR ADMINISTERING DRUG IN LIQUID FORM

To provide a clear liquid dosage form of substances.

(e.g. syrups and solutions)

11. FOR ADMINISTERING DRUG TO CHILDREN

For administration of drug in children and neonates who are unable to take tablets, or bear taste & odour of the medicine or the needle of the syringe.

(e.g. Flavored sweetened syrups and suspensions)

12. FOR EMERGENCY SITUATIONS

To deliver the medicine to patient on urgent basis especially in emergency situations.

(e.g. Injections or Infusions)

(Jibran Iqbal. Pharm.D / The Islamia University of Bahawalpur, Pakistan)

Answer 2

provide safe convenient delivery of accurate doses

protect the drug substance from environmental and biological factors

test masking