Semisolid Dosage formsOintments: are semi-solid greasypreparation for application to the skin ormucosa. The base is usually anhydrousand containing medicaments in solutionor suspension.They are generally used for theira. emollient effectsb. protection effect of lesionsc. topical application of medicationseg.Acne- Sulphur or resorcinol ointmentAntibiotic- bacitracine, chlortetracyclineAnti-inflammatory- BetamethasoneAnti-septic-Zinc oxideDandruffs- Salicylic acidCounter irritant- Capcisin
Creams have a significant risk of causing immunological sensitization due to preservativesCreams:These are semisolid emulsion forexternal use. There are two kinds,aqueous and oily cream, in which theemulsion are Oil in Water (O/W) orWater in Oil (W/O). The oil in water typeare relatively non-greasy.Cream are of two type cold cream andvanishing creams. Vanishing cream isan oil in water type of emulsion whereascold cream is of water in oil type ofemulsion. They also differ in their pH.vanishing cream is of neutral to slightlyacidic pH but cold cream is of neutralpH. Vanishing creams are easilywashable but cold creams can not beremoved from the skin easily.Creams have a significant riskof causing immunologicalsensitization due topreservatives
Gels/Jelly:Gel is semi-solid, jelly like materials thathave properties ranging from soft andweak to hard and tough.They aresubstantially crossed link system, whichexhibits no flow when in steady-state.Gels are aqueous colloidal suspensions ofthe hydrated forms of insolublemedicaments. Gels are thicker than asolution.They can use for both external and internalpurpose.Useful for the scalp and body folds. Avoidcuts and erosions due to drying andstinging effect of alcohol base.Example: Aluminum Hydroxide Gel, usedas an antacid.
•Paste:•Semi-solid preparation forexternal application.Paste combines three agents -oil, water, and powder. It is anointment in which a powder issuspended.Base may be anhydrous(liquid or soft paraffin) orwater soluble (glycerol andmucilage).Their stiffnessmakes them useful as aprotective coatings
Liniments: are fluid, semi-solid oroccasionally, semi-solid medicinalfluid rubbed into the skin tosoothe pain or relieve stiffness.They may be alcoholic or oilysolutions or emulsions. Most aremassaged into the skin (counter-irritant or stimulating types) butsome are applied on a warmdressing or with brush ( analgesicand soothing types).Liniment must not used inbroken skin.
Suppositories: Are conical or ovoid, solidpreparations for insertion into therectum where they melt, dissolved ordisperse and exert a local or less oftensystemic effect. Their basis is fat, a waxor glycerol-gelatin jelly .In past: small suppositories known ascones were prescribed for ear infection.A long and very narrow form, called asbougies, were used for nasal andurethral infections; these are virtuallyobsolete.
•Poultices:Poultices are paste likepreparations used to reduceinflammation as they retainheat. They are used externally.They are first heated (as hot asthe patient can bear) andapplied on a dressing of theaffected area.
Aerosols:Aerosol is a colloid suspension of fine solidparticles or liquid droplets in a gas. They areused to apply drugs to the respiratory tract andskin. They are mainly fluid or semi-fluidpreparations intended to be used on them skin.Most of them are used as antiparasitics.By applying pressure to the bulb of the deviceejection of the medicament as a mistsuspended in air occurs.The compressed rather than liquefied gasesmay be used to prepare aerosols. The pressureof the gas in the head space of the containerforces the product concentrate up the diptubes and out of the valve.Common gas use as propellant; nitrogen,carbon dioxide and nitrous oxide.
•Transdermal drug deliverysystem:•Transdermal patches can be a very precisetime released method of delivering a drug.These are devices in the form of adhesivepatches of various shapes and sizes (5-20cm) which deliver contained the drug atconstant rate into the systemic circulationvia stratum corneum.•The drug (in solution or in bound polymer)is held in a reservoir between occlusive andbaking film and rate controlling microsporemembrane, the under surface of whichsmear with and adhesive impregnated withpriming dose. The adhesive layer is backedby another film that is to be peeled ofbefore been application.
•Syrup:Liquid oral preparations in whichthe vehicle is a concentratedaqueous solution of sucrose orother sugar used to be calledsyrups .It is a thick, viscous liquidconsisting primarily of a solutionof sugar in water, containing alarge amount (65%) of dissolvedsugars but showing littletendency to deposit crystals.
•Solution:A solution is a homogeneousmixture composed of only onephase. In such a mixture, a solute isa substance dissolved in anothersubstance, known as a solvent. Thesolvent does the dissolving. Theparticles of solute in solution cannotbe seen by naked eye. Sterilesolutions can be used for parenteralpurposes and non sterile solutionscan be used orally.
•Tincture:A tincture is typically analcoholic extract of plant oranimal material or solution ofsuch or of a low volatilitysubstance. They are relativelyweak compared to extracts.Example:Tincture of iodine.
•Suspension:A suspension is aheterogeneous preparationcontaining solid particles thatare dispersed in fluid. Usuallythe solids must be larger than1 micrometer. The internalphase (solid) is dispersedthroughout the externalphase (fluid) throughmechanical agitation, withthe use of certain excipientsor suspending agents.
•Emulsion:An emulsion is a mixture of two ormore liquids that are normallyimmiscible (un-blendable). In anemulsion, one liquid (the dispersedphase) is dispersed in the other(the continuous phase).Types of emulsion:1.o/w emulsion oil is dispersedphase while water is dispersionmedia.2.w/o emulsion water is dispersedphase while oil is external phase3.multiple emulsion w/o/w o/w/o
•Lotion:Lotions are fluid preparations usedexternally without any friction orrubbing. They are either dabbed onthe skin or applied on a dressingand covered with water proofmaterial to reduce evaporation. Itis of low- to medium-viscosity,topical preparation intended forapplication to unbroken skin.
•Elixir:It is a clear, sweet-flavored liquidused for medicinal purposes, tobe taken orally and intended tocure ones ills. When used as apharmaceutical preparation, anelixir contains at least one activeingredient designed to be takenorally. They are pleasantlyflavored and attractively colored.
•Draughts:Draughts are liquid oralpreparations of which only oneor two rather large doses of theorder of 50ml are prescribed.Each dose is given in a separatecontainer. Pediatric form isexceptional so multiple dosevolume is prescribed.
•Enemas:Enemas are solutions, suspensionsor oil in water emulsions ofmedicaments intended for rectalpurposes. An enema has theadvantage over any laxative in itsspeed and certainty of action, andsome people prefer it for thisreason. Enemas can be carried outas treatment for medicalconditions, such as constipation .
•Gargles:Gargles are aqueous solutions usedto prevent or treat throat infections.Usually, they are dispensed inconcentrated form with directionsfor dilutions with warm water beforeuse. Antiseptic mouthwash are usedto remove bacteria from the throat.
Injections:An injection (often referred to as a"shot" or a "jab") is an infusionmethod of putting fluid into the body,usually with a hollow needle and asyringe which is pierced through theskin to a sufficient depth for thematerial to be forced into the body. Aninjection follows a parenteral route ofadministration; that is, administeredother than through the digestivetract.There are several methods of injectionor infusion, including intradermal,subcutaneous, intramuscular,intravenous, intraosseous, andintraperitoneal.
Intravenous bolus dosageform:Administering a drug intravenouslyensures that the entire dose enters thegeneral circulation. Intravenousadministration bypasses the absorptionphase and the hepatic first-pass effect.Bioavailability is therefore complete. Thedrug is then distributed throughout thebody and then eliminated by the liverand/or kidney. With an iv bolusadministration the amount of drugdelivery is precisely controlled
Eye drops are saline-containing drops used asa ocular route to administer. Eye dropssometimes do not have medications in themand are only lubricating and tear-replacingsolutions.Eye drops have less of a risk of side effectsthan do oral medicinesEar drops are a form ofmedicine used to treat orprevent ear infections,especially infections of theouter ear and ear canal.Bacterial infections aresometimes treated withantibiotics.Nasal drops are solution ofdrugs that are instilled in thenose with a dropper. They areusually aqueous as oilypreparations inhibit themovement of the cillia in thenasal mucosa.Drops