Introduction To Dosage Forms And Routes Of Administration Part B

Question 1

What is route of administration?

Answer 1

• path by which a medicine = taken into the body
• affects absorption
  Can be:
• oral
• parenteral
• rectal/vaginal
• topical
• respiratory

Question 2

What is absorption?

Answer 2

• process from when the medicine is administered to when the API reaches the bloodstream

Question 3

What is oral administration?

Answer 3

• most frequently used
• generally (systemic effects) - after drug absorption
• most convenient
• safe
• relatively slow onset of action - time taken
• stomach environment
• affected by gastric emptying time (dependent on weight)

Question 4

What is parenteral?

Answer 4

• not interal (another passage of entry besides the GI tract)
• consisted by the following routes:
• intravenous
• subcutaneous
• intramuscular
  Less common:
• intracardial
• intrathecal

Question 5

What are intravenous injections (IV)?

Answer 5

• into the vein (straight into the bloodstream)
• speed of action - acting immediately, safety concerns
• no absorption phase (100% bioavailability)
• irritant drugs can be administered

Question 6

What is bioavailability?

Answer 6

• the fraction of the administred dose that reaches the bloodstream ( impossible to get 100% orally)

Question 7

What are subcutaneous injections (s.c.)?

Answer 7

• administered into the subcutaneous tissue
• tissue immediately underneath the skin
• easy to self-administer

Question 8

What are intramuscular injections (i.m.) ?

Answer 8

• deeper than subcutaneous
• administer the dose into the muscle layer
• slower onset than IV (needs to be absorbed from muscles into bloodstream)

Question 9

What are rectal administrations?

Answer 9

• administered into the rectum
• for local action
• but also systemic (generalised action) - useful in some specific cases
  e. g. for a patient who is vomiting - especially for young children)

Question 10

What are vaginal administrations?

Answer 10

• for administeringinto the vagina
• mainly for local effects
• in some cases systemic

Question 11

What is a topical route?

Answer 11

• application to the skin
• for local action (e.g. anti fungal agents) - sction where applied
• used for systemic action - transdermal (not topical) (for the whole body)

Question 12

Why is local action advantageous?

Answer 12

• can address the problem with systemic side effects
• other routes (topical):
  Eye
  Ear
  Nose

Question 13

For ophthalmic routes, what is a requirement?

Answer 13

Sterility

Question 14

What are some respiratory routes?

Answer 14

• administration to the lungs
• useful for asthmatic problems
• particle size = important factor (how deep in the respiratory tract the medicine ends)
• specific devices needed for this administration (e.g. inhaler)