Suppository, Inserts, and Sticks Flashcards
Suppository
Solid DF
One or more API dispersed in suitable base
Molded formed into shape for insertion
Insertion in orificies for systemic or local effects
Inserts
Solid DF
insert naturally occurring body cavity other than rectum (w/ mouth or rectum)
Medication Sticks
convenient form of administration
Reasons for choosing rectal route:
- Patient cannot make use of the oral route
- The drug is not well suited for oral administration
- For localized treatment
Reasons for not using route
- Cultural acceptance
- Slow and incomplete absorbance of drug
- Inter- and intra- drug level variations
- Difficult for large- scale production
Why is water attracted with a resulting unpleassnt sensation ofor the patiens?
Due to osmotic effects
Enzyme not present in rectum resulting to greater stability of peptide-like drugs
Esterase or Peptidase
T/F. Penetration enhancers may be used in improve the absorption profile of the drugs
True.
How is drug from the rectum absorbed?
Through passive diffusion
Is the rate and extent of drug absorption in the rectum lower or higher than the oral route? Why?
Lower than oral Route due to small surface area of absorption
What vein in the hepatic system causes the first-pass effect?
Superior Hemorrhoidal Vein
What is the limitation of the use of surfactants in rectal drug delivery?
Surfactants may lead to irritation to the rectal mucosa
This delivery contains low amount of fluid and has limited buffer capacity
Rectal Drug Delivery
At what mL do rectally instilled preparations tend to be confined in the rectum or sigmoid colon? Then where does it travel after this?
About 50 mL, to the ascending colon if more mL
T/F. Drugs in rectal drug delivery are erratically absorbed.
True. They are unpredictable or incompletely absorbed.
Advantages of Rectal Administration
▶ First-pass effect
▶ Drug stability
▶ Large dose drugs
▶ Irritating drugs
▶ Unpleasant tasting or smelling drugs
▶ Pediatric use
▶ Unconscious, n/v
▶ Upper GIT disease
▶ Rapid drug effect system
Disadvantages of Rectal Administration
▶ Lack of flexibility of the dosage
▶ Expensive (high demand)
▶ Exhibit variable effectiveness
▶ Erratic absorption
▶ Dose of drug may be greater than or less than the dose of the same drug given orally
▶ Factors affecting dosing (anatomic and physiologic factor and physicochemical factors)
▶ Physiologic Factors and Drug effect (i.e. Circulation route and pH and lack of buffering capacity of rectal fluids, colonic content)
What factors affect the greater absorption in the rectum?
▶ fecal matter
▶ enema
▶ diarrhea
▶ colonic obstruction d/t tumor,
▶ tissue DHN
In Lipid - Water Partition Coeffcient of the drug, the base consideration is an important decision. What base is suitable for a lipophilic drug?
Fatty base
Physicochemical factors of the drug and base that affect rectal absorption
▶ lipid water solubility
▶ particle size
▶ lipid water partition coefficient in relation to suppository base
What base is suitable for a water soluble or oil soluble drugs?
Water - soluble drugs
Why are rectal suppositories have a thicker end?
To prevent expulsion when the sphincter contracts
How should the rectal drug be inserted in the rectum?
Inserted base or blunt end up
Absorption of rectum, a lipoidal system, is through the?
Superior vena cavaa
Where is rectal drug delivery dependent?
Physicochemical properties of Drug
Composition of Base
What is a useful measure for drug absorption?
Partition between suppository base and rectal fluid
How does uptake in rectal drug delivery occur?
Trancellular absorption via pH parition hypotheses
Use of Surfactants in Rectal Drug Delivery
Modify membrane permeability
enhance wetting and spreading of base
dissolution of the drug
What animal of choice is used in evaluation of rectal drug availability?
Dogs
In the treatment of local conditions like hemorrhoids, what base is widely used for rectal drug delivery?
Fatty ointments
What delivery forms are employed in the administration of drugs for systemic effects?
Tablets, capsules, microenemas
Characteristics of rectal suppositories in adults include:
tapered at one or both ends
weighing 2 g
bullter torpedo or little finger
32 mm (1.5 in.) long
What is the weight of pediatric rectal suppositories? What is its shape?
half the wt and size of adult
pencil shape
The 2 g weight for rectal adult suppositories is based on what suppository base?
Cocoa butter base
What indications of drug have systemic effect and administred rectally?
Sedatives, Tranquilizers, Analgesics
the largest OTC rectal suppositories
Hemorrhoidal treatment
classification of rectal suppository bases
fatty, water soluble, and water miscible
Shell suppositories similar to soft - gel capsules
Rectal capsules
They are of elongated shape and have a smooth external appearance that may be lubricated.
Rectal Capsules
For capsules, to achieve a systemic effect, how is it usually filled with?
Solution of suspension of the durg in vegetable oil or liquid paraffin
Why do rectal tablets have difficulty in disintegrating?
Due to low amount of water present in the rectum
Have difficulty disintegrating due to low amount of water present in the rectum
Rectal Tablets