A pharmaceutical dosage form is the entity that is administered to patient so that they receive an effective dose of a drug. It is a formulation that typically contains drug substance(s) and excipients in quantities and physical form designed to all the accurate and efficient administration of the drug substance to the human or animal patient.
Besides providing the mechanism for the safe and convenient delivery of accurate dosage, pharmaceutical dosage forms are needed for the following additional reasons:
1. To provide drug products that bypass the first-pass metabolism e.g., injections, topical dosage forms etc.
2. To protect the drug substance from the destructive influence of atmospheric oxygen or humidity e.g., coated tablets.
3. To protect the active pharmaceutical ingredients (APIs) from the destructive influence of gastric acid following oral administration of the dosage form e.g., enteric-coated tablets.
4. To mask the bitter, salty, or undesirable taste or odor of drug substances e.g., capsules, coated tablets, taste-masked suspensions, and flavored syrup.
5. To provide useful dosage form for administering substances that are either insoluble or unstable in the desired vehicle e.g., suspensions.
6. To provide rate-controlled drug action e.g., various controlled-release tablets, capsules, and suspensions.
7. To provide drug products that are stable, effective, and safe for consumption under specified suitable storage conditions e.g., powders for reconstitution.
8. To provide optimal drug action from topical administration sites g., creams, transdermal patches, ointments, and ophthalmic, ear, and nasal preparations.
9. To provide sterile, clear, and particulate-free liquid dosage forms of substances e.g., injections and eye drops.
10. To provide site-specific and local drug delivery e.g., rectal and vaginal suppositories.
11. To target the drug at the desired site of action e.g., nanoparticulate systems, liposomes, etc.
12. To achieve rapid onset of action through inhalation therapy e.g., inhalants and inhalation aerosols.
Allen, L. and Ansel, H (2014). Ansel’s Pharmaceutical Dosage Forms and Drug Delivery Systems (10th ed.). Philadephia: Lippincott Williams and Wlkins.
Mahato, R and Narang, A. (2018). Pharmaceutical Dosage Forms and Drug Delivery (3rd ed.).New York: Taylor & Francis Group, LLC.
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