Pharmaceutics II: Exam IIII Otic Preparations

Otics vehicles can be _______ or ________

Aqueous, non-aqueous

What are the two types of non aqueous vehicles?

Water miscible

water immiscible

What is an example of a Non aqueous water-miscible vehicle?

glycerol

What is an example of a non-aqueous water-immiscible vehicle?

mineral oil

Sterility (is/ is not) a requirement for otic preparations

is not

Multidose otic formulations (especially aqueous) require the inclusion of a __________ to prevent microbial growth

preservative

What are some example of preservatives?

-Chlorobutanol (0.5% w/w)

-Parabens (0.2% w/w)

-Benzalkonium chloride (0.002-0.02% w/v)

-Thiomersal (0.002-0.005% w/v)

T/F Most otic formulations are sterile

False, most are not

______ aids in administration and retention at the site of application (extends residence time). It also decreases the drainage of the drug from the middle ear to the nasopharynx

Viscosity

Viscosity aids in the administration at the site of application (_______ residence time). It also __________ the drainage of the drug from the middle ear to the nasopharynx

extends, decreases

What is an example of viscosity modifying agents?

Hydrophilic polymers (hyaluronate, PEG, propylene glycol)

__________ improves drugs stability against oxidation

antioxidants

Antioxidants improve drug's ________ against oxidation

stability

Otic preparations can be in a pH from ___-___

2-7.5

Because the ear is composed of ____, a wide range of pH is acceptable, ranging between 2-7.5

skin

pH is maintained by using suitable buffers, ____ or ____

HCL, NaOH

pH outside of 2-7.5 should be avoided because it will cause local ______ and the formulation may be _____

irritation, unstable

_______ is preferred to minimize irritation

Isotonicity

Generally, the pain and discomfort observed during application is associated with the nature of the medicament and infection rather than ____

tonicity

____ preparations are products used inside, outside or around the ears

Otics

What are the two divisions of the external ear?

-Auricle

-Tube/canal

___ the externally visible part of the ear

auricle

_____ leads from auricle to the temporal skull bone

tube/canal

What is the average volume of the tube/canal for children and adults?

0.3 for children, 1.5 for adults

_____ is material accumulation from oil secretions originating from the exocrine glands and maybe dirt accumulation from the external environment

Ear wax (cerumen)

Cerumen helps in ear canal ___________ and traps dust and dirt from the environment, _________ the inner ear

lubrication, protecting

If ______ is not cleaned away it can inhibit auditory sounds from reaching the dum

cerumen

Only the external ear is accessible for drug administration due to the presence of the ______ blocking any external access to the middle or inner ear.

drum (tympanic membrane)

_____ can take place through the drum

injections

What are the 2 things ear preparations treat?

-removal of cerumen

-treatment for ear infections, inflammation, or pain

Due to the outer ear's skin covered structure and skin related diseases, many formulations presented in the _____ and ______ can be adjusted or utilized for otic treatment

transdermal, topical delivery

Cerumen, if allowed to dry, forms a sticky semisolid that holds what could make its way into the ear canal.

-shed epithelial cells

-fallen hair

-Dust, and other foreign bodies

Excessive accumulation of cerumen in the ear may cause:

-itching

-pain

-impaired hearing

-impedes otological examination

If not removed periodically, the cerumen may become impacted and its removal made more _____ and _____

difficult, painful

Through the years ______, ______, and _____ have been commonly used to soften cerumen for its removal

light mineral oil, vegetables oils, hydrogen peroxide

Solutions of synthetic surfactants have been developed for their ability to remove earwax by ______ or _______ it

dissolving, emulsifying

What is an example of a otic preparation that removes earwax?

Carbamide peroxide in glycerin and propylene glycol (debrox drops, GSK)

The carbamide peroxide releases _______, which disrupts the integrity of the impacted wax, allowing its easy removal.

oxygen

__________: softens earwax in order to be removed by disrupting its integrity

Earwax removal aids

Cerumen removal usually involved:

-Placing the otic solution in the ear canal with the pts head tilted at a 45 degree angle

-Inserting a cotton plug to retain the medication in the ear for 15-30 min

-gentle flushing of the ear canal with lukewarm water using a soft rubber ear syringe

Earwax removal aids are usually made of which types of oils?

Light mineral and vegetable oils

Earwax removal aids can also be _____ such as _______ and _______

peroxides, carbamide peroxide, hydrogen peroxide

What is carbamide peroxide used for?

ear wax removal

T/F Earwax removal aids can also contain drugs for suppressing pain such as acetaminophen and local anasthetics

True

Earwax removal aids can also contain ____ agents such as docusate sodium or triethanolamine oleate

emulsifying

________ drugs are used topically in the ear for their anti-infective activity

Anti-infective, anti-inflammatory, and analgesic ear preparations

Drugs for local infections and inflammation include agents such as:

-Ciproflaxacin

-Colistin sulfate

-Neomycin

-Ofloxacin

-Polymyxin B sulfate

-Nystatin (fungal infections)

Agents for local infections are formulated into eardrops as (solutions or suspension) in a vehicle of ________ or __________

anhydrous glycerin, propylene glyclol

Local infection agents __________ cause them to draw moisture from the tissues, reducing inflammation and diminishing the moisture available for the life process of the microorganisms

hygroscopicity

To assist with relieving pain that frequently accompanies ear infections many anti-infective otic preparations also contain:

-Analgesic agents (antipyrine)

-Local anesthetics (pramoxine hydrochloride and benzocaine)

What are examples of anti-inflammatory agets?

-Hydrocortisone

-Dexamethasone sodium phosphate against swelling and inflammation

Some physicians prefer the use of corticosteroids in _______ form, packaged in ophthalmic tubes

ointment

Corticosteroid ointment packaged in ophthalmic tubes allows placement of ___ amounts of ointment in the ear canal with a minimum amount of waste

small

Commercial corticosteroid ointments packaged in ophthalmic tubes are labeled for ____ and _____ use

ear and eye

What antibiotics are most commonly used for local infections/inflammation?

-Oflaxacin

-Ciprofloaxacin

Antibiotics and corticosteroids are what type of mixture?

solution

Hydrocortisone and acetic acid are what types of agents?

antibacterial

Steroids and antibiotic combinations can be ______ or ______

solutions, suspensions

_______: polypeptide that penetrate into and disrupts the bacterial cell membrane

Colistin (3mg/ml)

________: amino glycoside antibiotic that inhibits protein synthesis, disrupting the normal cycle of ribosomal function.

Neomycin (3.3 mg/ml)

_________: corticosteroid hormone, controls inflammation, edema, pruritus, and other dermal reactions

Hydrocortisone (10mg/ml)

________: surface active agent that promotes tissue contact by dispersion and penetration of the cellular debris and exudates.

Thonzonium (0.5 mg/ml)

T/F earwax removal drops should be left in the ear

False, they should be removed with an ear syringe

Drops intended to treat _______ otitis infection are intended to be instilled and left in the ear

external

Maintaining the head tilt for several minutes after application helps the drops roll down _____ the ear

into

Some ear drops cause stinging upon administration because of their _____. Parents and children should be forewarned, especially if a child has __________ in the ear.

low pH, tympanostomy tubes

Formulation considerations for otic preparations:

-Therapeutic agent

-vehicle

-Sterility and preservation

-Viscosity

-Antioxidants

-pH Tonicity

Therapeutic agents include:

-Local anesthetic (benzocaine)

-Steroid (hydrocortisone)

-Antimicrobial agents (chloramphenicol)

-Earwax removal airs (carbamide peroxide)

-Analgesic (antipyrine)

-Dehumidifying agent (isopropyl alcohol)

Local anesthetic (________)

benzocaine

Steroid (________)

hydrocortisone

Antimicrobial agents (_________)

Chloramphenicol

Earwax removal airs (________)

carbamide peroxide

Analgesic (_______)

antipyrine

Dehumidifying agent (_________)

isopropyl alcohol