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Flashcards in Pharmacology Deck (15):
1

Which is quicker, intramuscular or subcutaneous?

Intramuscular

2

When you give a drug subcutaneously, how does it reach the systemic circulation?

Diffusion into capillaries or lymphatic vessels

3

Advantages of subcutaneous administration?

• Absorption is relatively slow (advantageous/disadvantageous) due to poor vascular supply
• Route of administration for many protein drugs (e.g. insulin)
• Suitable for administration of oil-based drugs (e.g. steroids)
• Can be used to introduce a depot of drug of drug under the skin that is very slowly released into the circulation [e.g. certain contraceptive steroids (medroxyprogesterone) and antipsychotic drugs (fluphenazine decanoate)]
• Relatively simple and painless
• Can be used when other routes of administration can no longer be tolerated.

4

Disadvantages of subcutaneous administration?

Disadvantages
• Injection volume limited (1-2ml)
• Possible inflammation or irritation at infusion site
• Possible leakage at site
• Possible allergic reaction

5

If your drug is lipophilic, potent and has a relatively brief half life, what is the best way to give it?

Transdermal patch

6

Advantages of transdermal drug delivery?

Steady rate of drug delivery, avoidance of first-pass metabolism, rapid termination of action (if t1⁄2 is short)

Good patient compliance

7

Disadvantages of transdermal drug delivery

Relatively few drugs suitable for TDD, allergies, cost

8

Drugs which you could give via transdermal patch?

Nicotine
GTN
Fentanyl
Estradiol

9

Electroporation

– Applies a short high voltage pulse
– Disrupts cell membrane
– Can enhance permeability of the skin by 4-fold

10

Iontophoresis

Applies a few mA to a small area of skin via an electrode.

11

Body site

Potency varies with thickness of stratum corneum

12

State of the skin

Lower potency in children/certain body sites

13

Which is more potent, a steroid cream or ointment?

Steroid ointment

14

1% hydrocortisone acetate, 0.1% hydrocortisone butyrate, which one is more potent?

0.1% hydrocortisone butyrate is POTENT!!

(1% hydrocortisone acetate is only mild!!)

15

Steroid hormones, lipophilic or lipophobic?

Lipophilic