drug dosage forms

Drug dosage formPresented by: Abid hussain

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DRUG DOSAGE FORMS

Dosage forms are a mixture of active drug component and nondrug component.

Types of dosage form• Liquid dosage form (solutions, syrups, suspensions, drops,

injection)• Solid dosage form(Capsule , tablets , powder)• Semisolid dosage form(Ointments, Creams, pastes, Gels)

Solid dosage form

1. CapsulesIt contain one or more medicinal substances enclosed with in a shell or container prepared from suitable form of gelatinCapsule has two types• Hard gelatin capsules• Soft gelatin capsules

Hard gelatin capsulesIt is made up of gelatin ,sugar and water. They are physically hard. The hard-shell gelatin capsules contain solid drugs Soft gelatin capsuleIt is made up of gelatin. Glycerin Or sorbitol are added to render gelatin elastic. The soft-shell gelatin capsules contain oils. These capsules are easily swallowed due to tasteless shell.

2. Tablets A tablet is a solid dosage form that is prepared by

compressing or molding of the drug into various sizes and shapes.

A polymer coating is often applied to make the tablet

Smoother, easier to swallow, to control release rate of active ingredient, to make it more resistant to the environment and enhance tablet appearance Tablet are often stamped with symbols ,letters,

and numbers which enable them to identified. Their sizes are from few millimeters to about centimeter

Some tablets are in the shape of capsule are called caplets.

Types of tablet

Tablets for oral administration Tablets for implantation (pellets)

Tablets for oral administration

Immediate release tablet: Release the drug substance immediate after ingestion

Delayed release tablet: The drug substance is not released until a physical event has occurred e.g. change in gut flora.

Chewable tablet: The tablets are placed in the mouth, chewed and swallowed e.g. Lozenges

Buccal tablet: These are designed to be placed in buccal cavity of mouth for rapid action.

Sublingual tablets: these are placed under tongue for rapid dissolution.

Effervescent tablets: The tablet contain sodium bicarbonate in addition to the drug substance. Before use they are dissolve in water.e.g. Acetylsalicylic acid

Tablets for implantation (pellets)

A small tablet that is prepared for insertion under the skin by giving a small surgical cut into the skin which is stitched after the insertion of tablets. The tablet must be sterile one.

Contraceptive tablets are formulated as implant

3. PowdersPowders are drugs or drug extracts that are dried and ground and converted into fine particles.Advantage Use both internally and externally Good chemical stability as compared to fluids Rapid onset of action Easy to swallow even in large bulk, espacially mixed with

drink food Economic Safe to children and elderly patients

Disadvantage Not suitable for drugs unstable in atmospheric condition Not suitable for bitter, deliquescent and hygroscopic drug. The dispensing of powder is time consuming.

Types of powder1)Divided powder 2)Bulk powder1)Divided powder: They are dispensed in form of individual doses and generally are dispensed in papers, metal foil and heat sealed plastic bags and other containers.

2. Bulk powder Oral powder: They are intended to be suspended or

dissolve in water or mixed with foods e.g. Antacid and laxatives

Dentifrices: They contain soap or detergent, mild abrasive and anticariogenic agent

Dusting powder: They are locally applying non toxic preparation that is intended to be dissolved in water prior to use as an antiseptic. They may be formulated for nasal, optic and vaginal use.

Insufflations: They are introduced in body cavity such as ear ,nose, throat, tooth socket.Insuffaltor is used to administer these products.

Liquid dosage form Liquid dosage forms are prepared: (1) By dissolving the active drug substance(s) in an aqueous or no aqueous (e.g. alcohol, ether, glycerin) solvent. (2) By suspensing the drug in appropriate medium.(3) by incorporating the drug substance into an oil or water phases.

Liquid dosage forms can be administered:• Topically - lotions or suspension applied to the

skin, eye drops, nasal drops, ear drops

• Orally (p.o.) - oral suspension and solution

• Parenterally -• subcutaneous injection (s.c.), • intramuscular injection (i.m.)• and intravenous administration (i.v.)

Solution

Solutions are prepared by dissolving a solid or liquid drug in distilled water Solutions are intended for topical, oral, and parenteral administration. Solutions for local administration usually called lotions.

Suspension A suspension consists of a dispersion of relatively coarse particles, usually in aqueous vehicle. Suspensions may be used for oral and topical administration. Like solutions, oral suspensions are useful in children and patients who cannot tolerate a solid dosage form.

DropsDrops are solutions, tinctures or mixtures of high-

potent drug substances Drops are prescribed in small quantity (10-30 g)Drops are intended to be administered orally or

externally(as eye drops, nasal drops and ear drops).eye drops (collyrium): Timolol nasal (nose) drops: Olynth 0,1%ear drops: Furotalgin

Emulsions

• Emulsions are two-phase systems consist of liquid drug substances.

They are classified as:• oil-in-water emulsion (O/W)• water- in-oil emulsion (W/O) Emulsions can be administered as topically, orally, and I.M.

Injection

• Injection is an infusion method of putting drug into the body with syringe or needle.

• It is usually administrated by parental route.

• It shows rapid action and may be used for unconscious or uncooperative patients.

Semisolid dosage forms

Semisolid dosage forms are products of semisolid consistency and applied to skin or mucous membranes for therapeutic or protective action or cosmetic function.

PHYSICAL PROPERTIES:a)Smooth textureb) Elegant in appearancec) Non dehydratingd) Non greasy e) Non hygroscopicf) Non irritatingg) Do not alter membrane / skin functioning

OINTMENTSThey are composed of fluid hydrocarbon meshed in a matrix of higher melting solid hydrocarbon, e.g. pertrolatum.According the place of application they are: 1) unguentum dermaticum 2) unguentum ophthalmicum 3) unguentum nasale

CreamsThese are either oil-in-water (O/W) or water-in-oil

(W/O) emulsions and contain preservatives to prevent bacterial and fungal growth. Easier to spread & remove.

The commonest preservatives are parabensOil-in-water emulsions rub into the skin and are

easily washed off Water-in-oil emulsions are greasier

GelsGels are semi-colloids which liquefy on contact

with the skinGels are transparent or translucent non-greasy

semisolid gels .Gels are a common form for acne preparations

(e. g. Acnederm)They are used as lubricant.

Pastes Pastes semisolid preparations

that contain a Larger Amount of Solids compared to ointments

Stiffer than ointments, remain in place after application & can absorb serious secretions

Zinc oxide paste, contains 25% ZnO in starch & white petrolatum, product is firm & can protect skin & absorb secretion