UNIT 4

Question 1

What is the intravenous technique?

Answer 1

Parenteral route-not in the digestive system (usually digested)
Intravenous- injected into the blood stream

Question 2

What are some advantages of the intravenous technique?

Answer 2

-Entire dose enters systemic circulation (100% bioavailability)- avoids ‘first pass’ effect
-immediate action
-Large volumes can be administered
- Can be used on unconscious patients
-Dependable and repeatable results

Question 3

What are some disadvantages of the intravenous route?

Answer 3

-requires a functioning cannula-can lead to infection or sepsis
-can cause local reactions of the site of the cannula
-Can cause distress in some patients-especially children
-More expensive than other routes
-Requires trained health care specialists to administer

Question 4

What is a gram positive bacteria?

Answer 4

Have a thick cell wall made up of 40 layers of peptiodoglycan. this gives strength to the cell but doesn’t inhibit the movement of molecules into the cell.

Question 5

What is a gram negative bacteria?

Answer 5

Usually have a thinner wall made up fro a single layer of peptidoglycan with an additional plasma membrane around the outside. This means that any drugs that target gram negative bacteria have to overcome the external membrane before they can get close to the cell.

Question 6

Label the gram positive bacteria

Answer 6

.

Question 7

Label the gram negative bacteria

Answer 7

.

Question 8

What is ibroprofun an example of?

Answer 8

A painkiller

Question 9

What is penicillin?

Answer 9

Antibiotic (the first antibiotic identified in 1928)- is a beta lactam which targets bacterial cell wall synthesis

Question 10

What are the uses of penicillin?

Answer 10

traditionally beta lactam antibiotics such as penicillin were only effective against gram positive bacteria, but advances in pharmacology has yielded wider spectrum varieties such as amoxicillin. because of the large range of different Beta lactam antibiotics, they are used on a wide variety of conditions (e.g. tonsillitis) caused by both gram positive and gram negative bacteria.

Question 11

What is the mode of action for penicillin?

Answer 11

Beta lactam antibiotics interfere with the production of bacterial cell walls. Peptidoglycan, which makes up cell walls of bacteria, is a carbohydrate linked with short peptide chains. beta lactam antibiotics bind to the enzymes which forms the links between different peptidoglycan subunits. this prevents the cell wall fro being produced and stops the bacteria from dividing. these drugs also inactivate inhibitors which prevent autolysis (bacterial cell suicide), meaning the process is no longer prevented and the cell kills itself. because of this double effect, beta lactam antibiotics are referred to as bactericidal.

Question 12

What is the administration for penicillin?

Answer 12

Different penicillins are absorbed in different amounts in the oral route, depending on their stability in acid and whether they bind to different foods in the gut, but most common varieties are given via the oral route. they can slo be given via intravenous injection, or intramuscular injection for a slow release preparation against slowly dividing organisms. penicillin usually have a relatively short half-life, so treatment can be up to 500mg 4 times a day.

Question 13

What are some common side effects of penicillin and what are these caused by?

Answer 13

-nausea
-vomiting
-Diarrhoea
-Stomach pain
These are mainly caused by the unabsorbed penicillin disturbing the normal gut bacteria.

Question 14

What are some examples of serious side effects (1 in 1000) to penicillin?

Answer 14

-redness and peeling of the skin over large areas
-stomach pain, fever and very watery diarrhoea with blood.
Between 1-10% of the population have an allergic hypersensitivity to penicillins, leading to rashes, hives and other signs of allergic reactions. in less then 0.05% of the pop, penicillins can induce anaphylaxis which is life threatening.

Question 15

what are some contradictions to using penicillin?

Answer 15

-Contradicted to patients with penicillin hypersensitivity. patients who are sensitive to penicillin have a 10% chance of being sensitive to other beta lactam antibiotics including cephalosporins as the patient is allergic to the beta lactam ring structure of the drug and its metabolites.

-90% of penicillins and above 60% of cephalosporins are excreted by the kidneys, so dosage may need to be altered for patients with renal impairment

Question 16

How can penicillin lose its effectiveness?

Answer 16

antibiotic resistance (so patient must take the full course of antibiotics to prevent thsi from happening)
-Beta lactam loses its effectiveness due to a change in teh target organisms
-Due to the production of an enzyme (Beta lactamase) this has caused resistance as it attacks the beta lactam ring and causes bacterial gene to be produced that are resistant to penicillin

Question 17

What has been made to overcome antibiotic resistance?

Answer 17

Semisynthetic Beta lactam antibiotics- have a beta lactam ring surrounded by other parts of the molecule so not allowing this specialised enzyme (beta lactamase) to bind.

Question 18

What are the uses of ibuprofen?

Answer 18

A non-steroidal anti-inflammatory drug that can be used to ease mild to moderate e pain, controls a fever and reduces inflammation and swelling

Question 19

What is the topical route for administering medication?

Answer 19

Placed on the outised of the body.

Question 20

What are some advantages of the topical route?

Answer 20

-very easy to use-can be self-administered
-non-invasive
- can be applied directly to the site of action.

Question 21

what are some disadvantages of the topical route?

Answer 21

-very slow absorption
-most drugs not lipid soluble or have a large molecular weight so cannot be absorbed through the skin.
-Can cause irritation of the skin.