Buccal/ Sublingual Drug Delivery Flashcards
What is the most typical and successful example of buccal/ SL drug delivery for systemic effect?
Nitroglycerin
What is the benefit of administering to the oral cavity?
Absorbed directly into systemic circulation and achieves fast onset
Where is sublingual administration restricted ?
Ventral surface of the tongue and floor of the mouth, limited area with faster absorption
What is the area of main focus in buccal administration?
Lining of the cheek, large area
What are the 5 characteristics of SL and Buccal application?
First systemic absorption Fast onset of action and easily ended administration Convenient application Limited absorption Special formulation
When is Buccal/SL administration appropriate?
Emergency use
To replace injections
Candidates with extensive a first pass metabolism
Uncooperative/unconscious patients
What is the major difference between the oral mucosa and the GI mucosa?
The thickness. There are multiple, stratified epithelial layers in the oral mucosa and only a single layer in the GI.
What are the three types of oral mucosa in the mouth?
Masticatory, lining and special.
What component of the oral cavity has the thickest epithelium/epidermis and what has the thinnest?
Buccal (Mean thickness of 580 mcm)
Epidermis (Mean thickness of 120mcm)
The epithelial cell membrane is ________ and the intracellular space is relatively ___________
Lipophilic
Hydrophilic
The mosaic of hydrophilic and lipophilic regions allow for two mechanisms of drug transport:
Transcellular (Lipophilic drug, directly trough cells)
Paracellular (Hydrophilic drug, longer)
The fast blood flow in the oral mucosa allows for what type of transfer and what are the critical factors involved?
Passive diffusion
Initial concentration and Membrane thickness
Name the 3 major glands that supply saliva.
Parotid, Sublingual and Submandibular
What pH range in the saliva creates the optimal environment for absorptive, nonionized drugs?
5.8- 7.4
What are the functions of saliva?
Digest, mineralized, lubricate
What are the three factors that effect drug penetration?
Drug Candidates
In vivo Conditions
Formulations
Solubility, partition coefficient, permeability, taste, good diffusion (small MW) and stability/irritability are all factors determining what?
Drug Candidates
What are the three main in vivo conditions?
Mucosa conditions, pH and saliva flow.
What characteristics in the drug formulation are necessary to consider?
Drug release, retention, taste, shape, size, texture and irritability.
The ________ the drug concentration in the saliva, the better the chance for drug concentration across the mucosa.
Higher
Do we want a smaller or larger molecular weight in our drug candidates?
Smaller; easier to penetrate
What are the 4 In vivo requirements, not including taste and low irritability?
Small molecules (200-300MW)
Small dosing (10-20mg)
Low therapeutic concentration
Short half life
What are the 5 formulation requirements?
Fast disintegration; fast drug availability; few excipients present; appropriate shape, size and texture; no interference with normal oral function.
What are the traditional formulations?
Solutions, tablets, sprays, film strips
This formulation allows a prolonged drug release but can also have a high drug loss from swallowing into the stomach.
Chewing gum
What are some ways to increase drug release in chewing gum?
Buffer, coating, solubilizing agents, solid dispersion and chewing vigor
What are some drug candidates for chewing gum?
Local: chlorohexidine, sulfonamides, fluoride
Systemic: Nicotine
This formulation is immobile, with prolonged drug release and less functional interference than most.
Bioadhesive tablet
What are in bioadhesive tablets that allow them to stick to the surface?
Hydrogels. They swell, stick and release drug
This formulation is an immobile system with prolonged release and is a unidirectional drug release.
Oral patch
What are the two types of oral patches?
Matrix
Reservoir
Release is constant in which formulation?
Oral patch
True Or False? The more excipients in the oral patch, the better.
False. Excipient selection is very important.
What are the 3 methods of quality control?
Content uniformity
Package conditions
Disintegration testing
*dissolution testing is unnecessary
Substances to facilitate drug absorption by having temporary, reversible effects on membrane, but have no active pharmacological agents.
Permeation Enhancers
What are four enhancement mechanisms?
Disruption of cell structure
Extraction of intracellular lipids
Formation of micelles
Inhibition of enzyme activity
