Advantages and disadvantages of topical route of drug administration pdf
File Name: advantages and disadvantages of topical route of drug administration .zip
- routes of drug administration advantages and disadvantages pdf
- Drug Administration
- Topical Route of Drug Administration: Advantages and Disadvantages
- Structural Biochemistry/Routes of Drug Administration
routes of drug administration advantages and disadvantages pdf
A topical medication is a medication that is applied to a particular place on or in the body. Most often topical administration means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes including creams , foams , gels , lotions , and ointments.
Topical medications may also be inhalational , such as asthma medications , or applied to the surface of tissues other than the skin, such as eye drops applied to the conjunctiva , or ear drops placed in the ear, or medications applied to the surface of a tooth.
The definition of the topical route of administration sometimes states that both the application location and the pharmacodynamic effect thereof is local. In other cases, topical is defined as applied to a localized area of the body or to the surface of a body part regardless of the location of the effect. Such medications are generally hydrophobic chemicals, such as steroid hormones. Specific types include transdermal patches which have become a popular means of administering some drugs for birth control , hormone replacement therapy , and prevention of motion sickness.
One example of an antibiotic that may be applied topically is chloramphenicol. If defined strictly as having local effect, the topical route of administration can also include enteral administration of medications that are poorly absorbable by the gastrointestinal tract.
One poorly absorbable antibiotic is vancomycin , which is recommended by mouth as a treatment for severe Clostridium difficile colitis. A medication's potency often is changed with its base. For example, some topical steroids will be classified one or two strengths higher when moving from cream to ointment.
As a rule of thumb, an ointment base is more occlusive and will drive the medication into the skin more rapidly than a solution or cream base. The manufacturer of each topical product has total control over the content of the base of a medication. Although containing the same active ingredients, one manufacturer's cream might be more acidic than the next, which could cause skin irritation or change its absorption rate.
For example, a vaginal formulation of miconazole antifungal cream might irritate the skin less than an athlete foot formulation of miconazole cream. These variations can, on occasion, result in different clinical outcomes , even though the active ingredient is the same. No comparative potency labeling exists to ensure equal efficacy between brands of topical steroids percentage of oil vs water dramatically affect the potency of topical steroid.
Studies have confirmed that the potency of some topical steroid products may differ according to manufacturer or brand.
An example of this is the case of brand name Valisone cream and Kenalog cream in clinical studies have demonstrated significantly better vasoconstrictions than some forms of this drug produced by generic drug manufacturers. In dermatology , the base of a topical medication is often as important as the medication itself.
It is extremely important to receive a medication in the correct base, before applying to the skin. A pharmacist should not substitute an ointment for a cream, or vice versa, as the potency of the medication can change.
Some physicians use a thick ointment to replace the waterproof barrier of the inflamed skin in the treatment of eczema, and a cream might not accomplish the same clinical intention. There are many general classes, with no clear dividing line among similar formulations. As a result, what the manufacturer's marketing department chooses to list on the label of a topical medication might be completely different from what the form would normally be called. A cream is an emulsion of oil and water in approximately equal proportions.
It penetrates the stratum corneum outer layer of skin wall. Cream is thicker than lotion, and maintains its shape when removed from its container. It tends to be moderate in moisturizing tendency. For topical steroid products, oil-in-water emulsions are common. Creams have a significant risk of causing immunological sensitization due to preservatives and have a high rate of acceptance by patients. There is a great variation in ingredients, composition, pH, and tolerance among generic brands.
Foam can be seen with topical steroid marketed for the scalp. Gels are thicker than liquids. Gels are often a semisolid emulsion and sometimes use alcohol as a solvent for the active ingredient; some gels liquefy at body temperature.
Gel tends to be cellulose cut with alcohol or acetone. Gels tend to be self-drying, tend to have greatly variable ingredients between brands, and carry a significant risk of inducing hypersensitivity due to fragrances and preservatives. Gel is useful for hairy areas and body folds. In applying gel one should avoid fissures in the skin, due to the stinging effect of the alcohol base. Gel enjoys a high rate of acceptance due to its cosmetic elegance. Lotions are similar to solution but are thicker and tend to be more emollient in nature than solution.
They are usually oil mixed with water, and more often than not have less alcohol than solution. Lotions can be drying if they contain a high amount of alcohol. Ointments have a water number that defines the maximum amount of water that they can contain.
They are used as emollients or for the application of active ingredients to the skin for protective, therapeutic, or prophylactic purposes and where a degree of occlusion is desired. Ointments are used topically on a variety of body surfaces. These include the skin and the mucous membranes of the eye an eye ointment , chest , vulva , anus , and nose.
An ointment may or may not be medicated. Ointments are usually very moisturizing, and good for dry skin. They have a low risk of sensitization due to having few ingredients beyond the base oil or fat, and low irritation risk. There is typically little variability between brands of drugs. They are often disliked by patients due to greasiness.
The vehicle of an ointment is known as the ointment base. The choice of a base depends upon the clinical indication for the ointment.
The different types of ointment bases are:. The medicaments are dispersed in the base and are divided after penetrating the living cells of the skin. Ointments are formulated using hydrophobic, hydrophilic, or water-emulsifying bases to provide preparations that are immiscible, miscible, or emulsifiable with skin secretions. They can also be derived from hydrocarbon fatty , absorption, water-removable, or water-soluble bases. Properties which affect choice of an ointment base are: [ citation needed ].
Paste combines three agents - oil, water, and powder. It is an ointment in which a powder is suspended.
Powder  is either the pure drug by itself talcum powder , or is made of the drug mixed in a carrier such as corn starch or corn cob powder Zeosorb AF - miconazole powder. Can be used as an inhaled topical cocaine powder used in nasal surgery. A shake lotion is a mixture that separates into two or three parts over time. Frequently, an oil mixed with a water-based solution needs to be shaken into suspension before use and includes the instructions: "Shake well before use".
Medication may be placed in a solid form. Examples are deodorant, antiperspirants, astringents, and hemostatic agents. Some solids melt when they reach body temperature e. Certain contraceptive methods rely on sponge as a carrier of a liquid medicine.
Lemon juice embedded in a sponge has been used as a primitive contraception in some cultures. Cordran tape is an example of a topical steroid applied under occlusion by tape.
This greatly increases the potency and absorption of the topical steroid and is used to treat inflammatory skin diseases. A tincture is a skin preparation that has a high percentage of alcohol.
It would normally be used as a drug vehicle if drying of the area is desired. Topical solutions can be marketed as drops, rinses, or sprays, are generally of low viscosity, and often use alcohol or water in the base.
Transdermal patches can be a very precise time released method of delivering a drug. Cutting a patch in half might affect the dose delivered. The release of the active component from a transdermal delivery system patch may be controlled by diffusion through the adhesive which covers the whole patch, by diffusion through a membrane which may only have adhesive on the patch rim or drug release may be controlled by release from a polymer matrix.
Cutting a patch might cause rapid dehydration of the base of the medicine and affect the rate of diffusion. Some medications are applied as an ointment or gel, and reach the mucous membrane via vaporization. Examples are nasal topical decongestants and smelling salt. From Wikipedia, the free encyclopedia. Medication applied to body surfaces. This article is about topical medications. For other uses, see Topic disambiguation.
This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources.
Unsourced material may be challenged and removed. Medical portal. Medical Reference. University of Maryland Medical System. Merriam-Webster dictionary.
Retrieved Retrieved Sep 4, Comprehensive Dermatologic Drug Therapy. WB Saunders. Expert Opinion on Therapeutic Patents. Delivery of Topical Therapies.
Given by injection into a vein intravenously, IV , into a muscle intramuscularly, IM , into the space around the spinal cord intrathecally , or beneath the skin subcutaneously, sc. Breathed into the lungs, usually through the mouth by inhalation or mouth and nose by nebulization. See also Introduction to Administration and Kinetics of Drugs. Many drugs can be administered orally as liquids, capsules, tablets, or chewable tablets. Because the oral route is the most convenient and usually the safest and least expensive, it is the one most often used.
A diverse range of dosage forms and delivery systems has been developed to provide for the care and welfare of animals. The development of dosage forms draws on the discipline of biopharmaceutics, which integrates an understanding of formulations, dissolution, stability, and controlled release pharmaceutics ; absorption, distribution, metabolism, and excretion pharmacokinetics, PK ; concentration-effect relationships and drug-receptor interactions pharmacodynamics, PD ; and treatment of the disease state therapeutics. Formulation of a dosage form typically involves combining an active ingredient and one or more excipients; the resultant dosage form determines the route of administration and the clinical efficacy and safety of the drug. Optimization of drug doses is also critical to achieving clinical efficacy and safety. The PK and PD phases are linked by the premise that free drug in the systemic circulation is in equilibrium with the receptors.
Table 1: Pros and cons of different routes of drug administration. Route. Advantages. Disadvantages. Oral. • Easy. • Preferred by patients. • “Slow-release”.
Topical Route of Drug Administration: Advantages and Disadvantages
In this guide, we summarise the most common routes used to administer drugs, the advantages and disadvantages of each drug route and examples of dosage forms that are used to deliver the active drug to the intended site of action in the body. Oral Route 2. Sublingual Route 3. Buccal Route 4.
Structural Biochemistry/Routes of Drug Administration
Topical route of drug administration refers to the application of medication to the surface of the skin or mucous membrane of the eye, ear, nose, mouth, vagina, etc. Drugs for topical application are usually available as creams, ointments, gels, lotions, sprays, powders , aerosols, liniments, and drops. Topical route of administration provides a high local concentration of the drug without affecting the general circulation. However, absorption into the systemic circulation is very common and can lead to adverse effects. Sometimes, this systemic absorption is made use of, for its therapeutic value.
Before administering a medicine, it is important to understand the benefits and limitation of the routes of administration. This article, the first in a two-part series on medicines administration, offers a quick guide. Medicines administration is a core responsibility of registered nurses in healthcare settings and is increasingly being undertaken by nursing associates. Before administering any medicine, the person carrying out the procedure must be familiar with the advantages and limitations of the prescribed route and know the indications, contraindications and side-effects of the medicine they intend to give. This article, the first in a two-part series, provides an update on the routes of administration.
Topical route of drug administration refers to the application of medication to the surface of the skin or mucous membrane of the eye, ear, nose, mouth, vagina, etc. Drugs for topical application are usually available as creams, ointments, gels, lotions, sprays, powders , aerosols, liniments, and drops. Topical route of administration provides a high local concentration of the drug without affecting the general circulation. However, absorption into the systemic circulation is very common and can lead to adverse effects. Sometimes, this systemic absorption is made use of, for its therapeutic value. Useful for local delivery of agents, particularly those which have toxic effects if administered systemically. Avoidance of first pass metabolism.
In this guide, we summarise the most common routes used to administer drugs, the advantages and disadvantages of each drug route and examples of dosage forms that are used to deliver the active drug to the intended site of action in the body. Oral Route 2. Sublingual Route 3. Buccal Route 4. Intravenous Route 5. Intramuscular Route 6.