Chapter 6 - Topical Anesthetic Agents
. To achieve the optimal anesthetic effect, topical anesthesia should remain at the site of application for _______.
1-2 min
tetracaine hydrochloride - 1.classification 2. concentrations 3. onset of action 4. duration 5. considerations 6. MRD
1. ester 2. 2% 3. slow- peaks at 20 min 4. 45 min 5. plasma metabolized and in kidneys,lactation, lipid soluble, rapidly absorbed in local tissues 6. 20mg; 1mL 2% solution
benzocaine- 1.classification 2. concentrations 3. onset of action 4. duration 5. considerations 6. MRD
1. ester 2. most common is 20% but varies 6-20 3. rapid- 30 sec- peak is 2 min 4. 5-15 min 5.methemoglobinemia, mostly kidney excretion, no kids younger than 2, breast milk 6. none
dyclonine hydrochloride- 1.classification 2. concentrations 3. onset of action 4. duration 5. considerations 6. MRD
1. ketone 2. .5 or 1 % 3. slow- up to 10 min 4. 30 min .. even an hour 5. recommended dose during lactation 6. 200mg
lidocaine- 1.classification 2. concentrations 3. onset of action 4. duration 5. considerations 6. MRD
1. lidocaine 2. 2% or 5% 3. 2-10 min 4. 15-45 min 5. liver and kidneys, breast milk, follow manufacturer directions 6. 200 mg
topical penetrates how far
2-3mm
EMLA: composition? classification? onset action? duration? MRD? excretion?
2.5 lidicaine and 2.5 prilocaine amides 1 hour none for intraoral use not intraoral liver only for intact skin
oraqix: contains? classified as? concentration? onset? duration? mrd? metabolism? considerations?
2.5 lidocaine and 2.5 prilocaine amides 30 sec 20 min 5 cartridges during 1 tx liver do not inject
. A patient who has just been administered Oraqix gel (2.5% lidocaine and 2.5% prilocaine) can expect a comfortable duration of anesthesia of approximately _______.
20 min
Oraqix gel (2.5% lidocaine and 2.5% prilocaine) produces an anesthetic effect within ____________.
30 sec
Drying the mucosa with 2 × 2 gauze, prior to the application of topical anesthesia, assists in _______.
accurate placement of the topical anesthetic and increasing visibility
which topical can cause methemoglobinemia
bencozaine
Which topical anesthetic has the most rapid onset of action?
benzocaine
what topical doesnt always require prescription
benzocaine
cetacaine - contains what?onset? duration? MRD? excretion? classified as
benzocaine, Butamben, Tetracaine very rapid, lipid soluble- 30 sec 30-60 min spray 1 sec 200mg gel or liquid cholinesterase hydrolysis esters
. A toxic overdose of topical anesthetic may result in which of the following?
bradycardia- slow heart beat
localized adverse reactions of topicals are
burning stinging, sloughing, discoloration, irritation, temporary change in taste
concentrations OTC
can be as high as those in office
if plasma concentration are too high, what systems will be affected?
cardio and CNS
combinations used
cetacaine, EMLA, Oraqix
methods of delivery
cotton top applicator, spray, brushes, patches, blunted cannulas, single dose swabs
MRD for topicals
difficult to monitor, patches are a good way to monitor, doesnt exist for all topicals
which is a ketone?
dyclonine hydrochloride
common forms of topical
gel, ointment, spray, cream, liquid, lozenge
considerations for topicals- symptoms OD, whos at risk??
higher risk of toxicity children elderly and medically compromised. pale gray or blue skin, fatigue, shortness of breath, headache and lightheadedness( metho) people with breathing problems also at risk
what isnt benzocaine available as?
injectable
EMLA used for what
intact skin
which topical has US food and drug admin pregnancy category B?
lidocaine/prilocaine
what delivery method decreases metho risk?
metered spray with disposable nozzle
eutectic mixture is
mixture of 2 elements that together have a lower melting temperature than any individually
topical properties
no damage to tissue, acceptable taste, no systemic toxicity, remains at site
properties of topicals
no vasoconstr- ctor and more potent than injectable, block nerve conductions on the surface- decreased permeability of sodium ions to nerve cell- decrease depolarization- blocks nerve impulse
Which of the following is a eutectic mixture that will thicken into a gel once inserted into a periodontal pocket, relieving pain associated with nonsurgical periodontal therapy?
oraqix
benefits of single doses
prevents cross contam, less mess, doses monitored
purpose topicals
provide pain control conventional local anesthetic injections, needle insertion
Allergic reactions to topical anesthetic are _______.
rare
The FDA has released a Public Health Advisory alerting consumers to the potential
risk of life-threatening or fatal reactions to over-the-counter topical anesthetics
toxic OD of topical
seizures, unconsciousness, respiratory arrest, hypotension, cardiac arrest
Topical anesthetics are available in a variety of forms. Which method of delivery is most likely to produce a toxic reaction?
spray
Mild allergic reactions to topical anesthetic can include _______, _______, and _______.
swelling, raised welts, itching
Which topical anesthetic has the longest average duration?
tetracaine hydrochloride
most potent topical
tetracaine hydrochloride