22: Mucosal Flashcards by Brooke Thornburg

mucosal drug delivery

-via accessible body cavities covered with mucosa
-oral, nasal etc
-systemic or local
-mucoadhesion

How well did you know this?

Not at all

Perfectly

Advantages of mucosal drug delivery

-avoid first pass
-non-invasive
-ease/convenience

How well did you know this?

Not at all

Perfectly

disadvantages of mucosal delivery

-small area of absorption
-taste
-limited by weight of drug
-local tissue irritation, sensitivity to pathologic conditions

How well did you know this?

Not at all

Perfectly

Mucus

-secreted by goblet cells or salivary glands
-mostly water, mucins, lipids, salts
-diffusion barrier for drugs
-target for mucoadhesionm

How well did you know this?

Not at all

Perfectly

mucus functions

-coats all entry points to human body not covered by skin
-protects underlying epithelial tissues
-keeps mucosal membrane moist = lubrication

How well did you know this?

Not at all

Perfectly

Mucin

-highly glycosolated proteins
-large molecules either membrane bound or secreted
-provides gel-like structure of mucus
-carries negative charge attributed to high content of sugar

How well did you know this?

Not at all

Perfectly

Mucin structure

-cystein rich subdomains
-disulfide bonds
-protein and sugars

How well did you know this?

Not at all

Perfectly

Mucoadhesion

-state in which polymers and mucus are held together by interfacial forces
-prolongs residence time

How well did you know this?

Not at all

Perfectly

Mucoadhesion purposes

-controlled release
-enhance poorly absorbed drugs
-immobilization of the dosage form at desired state of action

How well did you know this?

Not at all

Perfectly

Mechs of mucoadhesion

-electrostatic interaction
-hydrogen bonding
-covalent bonding
-physical interpenetration

How well did you know this?

Not at all

Perfectly

Electrostatic interaction

-positive charged polymer + negative charged sialic acid in mucin

How well did you know this?

Not at all

Perfectly

Hydrogen bonding

-COOH
-OH
-NH2

How well did you know this?

Not at all

Perfectly

Covalent bonding

-disulfide bond between thiolated polymer and cysteine-rich portion of mucin

How well did you know this?

Not at all

Perfectly

Structures?

slides 13-15

How well did you know this?

Not at all

Perfectly

Oral mucosal

-systemic or local
-sublingual and buccal mucosa

How well did you know this?

Not at all

Perfectly

oral mucosal advantages

-avoid first-pass effect
-rapid absorption and onset of drug effect
-easy to remove if therapy needs to be discontinued

How well did you know this?

Not at all

Perfectly

oral mucosal disadvantages

-small surface area not good for low potency drugs
-limited by taste

How well did you know this?

Not at all

Perfectly

slide17

How well did you know this?

Not at all

Perfectly

Sublingual oral mucosal

-relatively permeable
-rapid onset
-more saliva = more mucus
-suitable for freq dosing and short-term delivery

How well did you know this?

Not at all

Perfectly

Buccal oral mucosal

-less permeable than sublingual
-slower absorption and onset
-less influenced by saliva
-suitable for sustained delivery applications
-buccal tablets, patches, semisolids

How well did you know this?

Not at all

Perfectly

Drug absorption via oral mucosal

-epithelium is a barrier
-transcellular
-paracellular by lipids
-absorbed into reticulated and jugular veins = drained into systemic circulation = avoid first pass

Drugs delivered via oral mucosa

-mostly lipophillic
-mostly small molecular weight drugs
-MAYBE hydrophillic macromolecular weight drugs such as peptides, oligonucleotides, polysaccharides but they likely need enhancers bc saliva enzymes

Buccal tablets

-bioadhesive polymer layer
-matrix w active ingredient and excipients

Buccal tablet examples

-Oravig for candidiasis
-Fentora for fentanyl (take buccal first then sublingual if u can handle it)

when taking buccal tablet do NOT

-crush, split, suck, chew, swallow

Actiq

-fentanyl citrate -lozenge on a stick -rotate and dissolve against oral tissue -for transmucosal or GI absorption

Buccal patches

-thinner and more flexible -less obtrusive, pt like them more

Nasal mucosal advantages

-avoid first pass -rapid absorption -easy

nasal mucosal disadvantages

-possible tissue irritation -rapid clearance from nose -cold or allergies can mess this up -limited surface area

Nasal mucosal examples

-Zicam for cold -Miacalcin for osteoporosis

Nasal cavity regions

-respiratory -olfactory

nasal respiratory region

-main site for systemic drug delivery -relatively large surface area -epithelium w mucus that lubes and warms air and removed foreign particles

nasal olfactory region

-small surface area -provides direct connection between CNS and atmosphere -small glands that produce solvent for odorous substances

Nasal systemic mucosal delivery

-via respiratory region -fast and extended drug absorption -analgesics, CVD, hormones, anti-inflammatory and anti-viral

Local nasal mucosal drug delivery

-treat topical nasal disorders -antihistamines and corticosteroids for rhinosinusitits -decongestants for colds

Nasal vaccines

-lymph tissue under nasal epithelium rich w dendritic cells, t cells, b cells bc it first site of contact w antigens -vax against respiratory infections

potential route for nasal drug delivery to CNS

-via olfactory region

Vaginal mucosal drug delivery

-permeation across epithelial membrane -gel, creams, films, rings

vaginal delivery advantages

-rich blood supply -high permeability -avoidance of hepatic first pass

disadvantages of vaginal admin

-hormone-dependent changes -pH

vaginal gels and creams

-leaky, messy, need applicator -estrogen, spermicide

Intrauterine drug delivery

-IUD in uterine cavity -progesterone and levonorgestrel -local effects in uterine cavity -5 years

rectal drug delivery

-drugs normally admin by oral can be put here too ! :) -local: IBD -systemic: when u cant do oral -less popular now -kids and olds

Rectal dosage forms

-suppositories (solid that melts/dissolves) -rectal emenas (liquids)

Ocular drug delivery

-local is greatly needed bc blood-retina barrier

Requirements for ocular drug delivery

-need to be clear -good corneal penetration -prolonged contact time w corneal epithelium -simplicity of use -comfy

Challenges in ocular delivery

-loss due to dilution in tears, spillage, drainage -short residence time -not much flexibility in terms of pH, osmolarity, solubility

Ocular dosage forms

-eye drops -ointments -ocusert -contacts -implants

How to improve eye drops

-viscosity enhancers to reduce drainage

Port delivery system

-permanent refillable implant -insicion in eye -flange, sealing septum, body, porous release control element