Term
| what are the general rules for using topical therapy? (4) |
|
Definition
1. know what you are treating
2. know your lesions
3. know your products
4. DO NO HARM |
|
|
Term
| For trans dermal delivery, the drug must be able to penetrate the _________ or be able to dissolve in and pass through the _____ ________ |
|
Definition
| keratinocyte; lipid bilayer |
|
|
Term
| what structures in/on the skin can the drug gain access throough? |
|
Definition
|
|
Term
| what factors determine of the drug diffuses across the barrier? |
|
Definition
1. concentration of drug
2. size of molecule
3. solubility of drug in vehicle
4. diffusion coefficent |
|
|
Term
| how can a vehicle aid in transfusion of a drug across a barrier? |
|
Definition
1. moisturizing
2. being lipid soluble
3. organic solvent to remove lipid bilayer
4. keratolytic to remove stratum corneum |
|
|
Term
| (T/F) A vehicle can penetrate on its own, thus making it perfect to carry drugs across the barrier |
|
Definition
|
|
Term
| What non drug factors influence absorption? (4) |
|
Definition
1. inflammation of skin
2. occlusion
3. thickness of skin
4. surface area covered |
|
|
Term
| what are the types of vehicles? (7) |
|
Definition
1. water based
2. sprays
3. lotions
4. emulsions
5. gels, creams, ointments
6. powders
7. water miscible bases |
|
|
Term
| What are some adverse effects of topical treatments? (4) |
|
Definition
1. dehydrate or macerate the skin with prolonged wetting (water-based)
2. may cause irritation (water miscible bases)
3. local cutaneous atrophy and alopecia (steroids)
4. glucocorticoid effects from systemic absorption (steroids) |
|
|
Term
| what are the 3 types of skin lesions? |
|
Definition
1. acute
2. subacute
3. chronic |
|
|
Term
|
Definition
| erythematous to erosive and often exudative |
|
|
Term
| describe a subacute lesion |
|
Definition
|
|
Term
| describe a chronic lesion |
|
Definition
| thickened with excess stratum corneum (elbow calluses) |
|
|
Term
| what type vehicles/topicals are contraindicated for what types of lesions? |
|
Definition
1. occlusive vehicles souldnt be used on acute lesions
2. do not use steroids on bacterial or fungal lesions |
|
|
Term
| (T/F) antipruritics can only be used focally, not on the entire body |
|
Definition
|
|
Term
| What characteristics do the ingredients of antipruritics have? |
|
Definition
1. corticosteroids
2. oatmeal
3. topical anesthetics
4. alter cutaneous sensation |
|
|
Term
| when are corticosteroids mostly used? |
|
Definition
|
|
Term
| why are steroids more potent in ointment vehicles? |
|
Definition
| aids in percutaneous penetration |
|
|
Term
| Relative potency of steroids |
|
Definition
hydrocortisone: (1.0) short
prednisone : (4.0) intermediate
triamcinolone: (25) long
dexamethasone: (25) long
betamethasone: (25) long
flucinolone: long |
|
|
Term
| Rational approach to the use of topical steroids |
|
Definition
1. use only when steroids is indicated
2. acute dermatoses affecting small area
3. potent steroids for short period of time
4. hydrocortisone for chronic topical use 5. monitor refills
6. client education |
|
|
Term
| properties of lime and tar sulfur antipruritic |
|
Definition
-antiseborrheic
-antiparasictic
-antifungal |
|
|
Term
| why do we use topical drugs? |
|
Definition
| to allow systemic access without having to give medication orally |
|
|
Term
| what type of animals is it hard to administer topical drugs |
|
Definition
|
|
Term
| what will inactivate many topical ingredients |
|
Definition
| purulent material and organic dibris |
|
|
Term
| what must you assume when applying a topical medication? |
|
Definition
| the animal will likely ingest it |
|
|
Term
| Characteristics of a water based vehicle |
|
Definition
-rehydrate, moisturize
-only needs 10-15 min contact
-come in shampoos, sprays, soaks, and rinses |
|
|
Term
| characteristics of sprays |
|
Definition
-water basd or other liquid vehicle
-allows for regional treatment
-mostly anti-itch or anit-microbials |
|
|
Term
| characteristics of a lotion |
|
Definition
-solution (ingredient doesn't settle)
-suspensions (need to shake before use) |
|
|
Term
| Characteristics of emulsions |
|
Definition
-oil in water
-occlusive and greasy |
|
|
Term
| characteristics of gels, creams, ointments |
|
Definition
-occlusive (ointments most)
-increases adsorption of active ingredient |
|
|
Term
| characteristics of powders |
|
Definition
-messy
-mostly used to treat ectoparasites
-poor percutaneous absorption |
|
|
Term
| characteristics of water miscible bases |
|
Definition
-propylene glycol
*enhances absorption
*organic solvant/vehicle
*keratolytic
*hygroscopic
-DMSO
*organic solvent
*hygroscopic
*bacteriostatic
*penetrates the stratum corneum |
|
|
Term
| What is the mechanism of action for local anesthetics? |
|
Definition
| conduction blockade- slows rate of depolarization of nerve through blocking sodium receptors |
|
|
Term
| (T/F) there is no alteration of resting membrane potential or threshold potential with conduction blockade |
|
Definition
|
|
Term
| what does it mean by slowed rate of depolarization? |
|
Definition
| atleast 3 consecutive nodes of rancier have been blocked and so the threshold potential is not reached and action potential is not propagated |
|
|
Term
| what would affect the anesthetics ability to block a tissue and why? |
|
Definition
| infected or inflamed tissue lowers the pH which interferes with the drug in both ionized and polar forms |
|
|
Term
| how does the drugs state of ionization relate to the blockade process? |
|
Definition
| The drug passes through the bilipid membrane in the polar form and the ionizes the block the channel once in the receptor |
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