Intro DDS

Question 1

What is the definition of DDS?

Answer 1

Drug delivery system

A device/formulation that brings a therapeutic agent to a body site at a certain rate to achieve an effective concentration

Question 2

What are the types of DDS?

Answer 2

Solids: Powders, Capsules, Tablets, Inserts
Semi-solid: Cream, Ointment, Gel, Suppositories
Liquid: Solution, Suspension, Emulsion (IV), Tincture, Elixier, Syrup, Lotion, Aromatic water
Gaseos: Aerosol, Inhaler spray

Question 3

Routes of administration:

Answer 3

Intravascular (IV): direct into blood, no absorption step
-Parental: intravenous, intra-arterial, intra-cardiac injections

Extravascular (EV): absorption step, then into the blood
-Mucosal: nasal, ocular, respiratory, sublingual, buccal, vaginal, rectal
-Dermal: through the skin
-Oral (portal circulation -> hepatic first pass)
-Other parental (IM, IP, ID, SC)

-Topical ( can be administered IM, ID, SC with topical effect, bc the pain, is locally (in the muscle, skin)

Question 4

What are the (other) external paternal routes?

Answer 4

IM (intramuscular): has to pass Muscle before it gets into the blood
SC (subcutaneous): pass Fat below the skin
IP (intraperitonial): pass Abdominal cavity
ID (intradermal): pass SKIN

Intrathecal (cerebrospinal fluid)
Intraarticular (joints)
Intraocular (eyes)

Question 5

What is the hepatic first-pass effect?

Answer 5

Drugs taken orally -> Nutrient-rich blood is transported to the liver by the portal vein -> in the liver it can be metabolized by enzymes -> the dose that has been taken is not going to rich the site

Question 6

How to overcome the big strong hepatic first-pass effect?

Answer 6

Some drugs are more effected than others
-> change route of administration
-> increase dose

Question 7

Which route is the most significant?
and what are the advantages and disadvantages?

Answer 7

Oral route
Advantage: natural, convenient, safe, designed for absorption (like nutrients)

Disadvantages: slow response, irregular absorption -> Bioavailability (rate of absorption),
destruction by enzymes in the stomach (bad for peptide and protein drugs) or by pH, GI irritant

Question 8

Pros and Cons for the parental route?

Answer 8

(+): faster, avoids poor GI absorption (hepatic first-pass and degradation), avoids Gut irritation, some drugs have a local effect, some long-acting drug delivery systems

(-): proper technique required, can be painful, not removable, significant side effects, costly to produce

Question 9

Important characteristics of IV administration?

Answer 9

-Intravascular
-Bioavailability: 100%, rapid absorption

-IV Bolus: avoid first pass -> instant effect but side effects occur rapidly
-IV infusion: controlled concentration of drug but possible tissue damage

Question 10

Important characteristics of IM administration?
Why is it better compared to SC?

Answer 10

-Extravascular
-Bioavailability: F= 0-100, fast absorption

-easier to use, Larger volume (2-5 ml) can be used compared to SC (< 1 ml)
-faster absorption due to more blood supply in the muscle
-self-injectable

(-): painful, Deltoid has more blood flow than gluteus -> rate varies with blood flow

Question 11

Important characteristics of SC administration? (< 1 ml)
Why is it better compared to IV?

Answer 11

-Extravascular
-Bioavailability: F= 0-1, absorption is slow

-easier to inject than IV -> self-administration e.g. Insulin
(-): limited volume, rate depends on blood flow, tissue damage after overuse

Question 12

What is pharmacokinetics?

Answer 12

Study of characterization of the time course of the
absorption, distribution, metabolism, and excretion (ADME) of drugs

Question 13

What is Biopharmaceutics?

Answer 13

-properties and dosage form that influences the release of the drug for biological activity

-the interrelationship between physicochemical properties (solubility logP+logD), the dosage form, and route of administration and how it affects distribution, absorption, and elimination

Question 14

What is Clinical Pharmacokinetics?

Answer 14

applying pharmacokinetic principles in the treatment of individual patients in optimizing drug therapy

f.e.: Metabolism -> you have a diuretic patient and the liver is not working well, so the drug is not going to be metabolized well -> adjust the therapy (dose)

Question 15

Explain LADMER:

Answer 15

(L)iberation (A)bsorption (D)istribution (M)etabolism (E)xcretion (R)elease

LADME = Biopharmaceutics
ADME = Pharmacokinetics
LADMER = Pharmacodynamics

Question 16

ADME explained:

Answer 16

Absorption: Uptake on site of administration into the blood
Distribution: Transfer from blood to extravascular fluids and tissues
Metabolism: enzymatic transformation to metabolic products, more ready to be excreted
Excretion: removal through urine, feces, saliva, sweat, milk

METABOLISM + EXCRETION = ELIMINATION

Question 17

Difference between Efficacy and Potency?

Answer 17

Efficacy: Does it work? The ability of a drug to produce the therapeutic effect

Potency: Amount of drug needed to produce an effect
The higher the potency, the lower dose is needed

Question 18

Important DDS and the route of administration:

Answer 18

Emulsion - IV - intrav.
Solution or drops - Topical/otic/ophthalmic - EV
Aerosol - Inhalational - EV
Suppositories - vaginal/rectal - EV

Question 19

NARCAN consists of Naloxone -> (an opioid antagonist - needed in an emergency overdose)
Why are no tablets available, rather a nasal spray or injection on the market?

Answer 19

Because of low bioavailability caused by the hepatic first-pass effect