CLASSES OF ABX: TETRACYCLINES

Question 1

Examples

Answer 1

• Doxycycline
• Demeocycline
• Lymecycline
• Minocycline
• Oxytetracycline
• Tetracycline
• Tigecycline

Question 2

MOA

Answer 2

Inhibits bacterial protein synthesis
Binds to ribosomal 30S subunit

Question 3

What spectrum

Answer 3

broad-spectrum bacteriostatic action.

Question 4

indications

Answer 4

• Chlamydia
• Rickettsia
• Acne
• Rosacea

Question 5

Doxycycline

Answer 5

Malaria + Chlamydia
OD
Taken with food

Question 6

Minocycline

Answer 6

Broader spectrum
Rarely used

Question 7

Tigecycline

Answer 7

Antibiotic that is structurally related to tetracyclines

Question 8

Side effects

Answer 8

• DNV
• Antibiotic-associated colitis
• Dysphagia
• Oesophageal irritation
• Hepatotoxicity
• Blood disorders
• Photosensitivity, hypersensitivity.
• Lupus-erythrematous-like syndrome and irreversible pigmentation
• Benign intracranial hypertension
• Teeth discoloration and bone deposit

Question 9

Lupus-erythrematous-like syndrome and irreversible pigmentation

Answer 9

Highest risk of minocycline

Question 10

Benign intracranial hypertension

Answer 10

Headaches
Visual disturbances
STOP

Question 11

Teeth discoloration and bone deposit

Answer 11

Do not give children under 12 or pregnant women

Question 12

Under 12 doxy

Answer 12

Do not give
- Deposits in growing bone and teeth.
- Causes teeth discolouration + dental enamel (hypoplasia)

Question 13

Contraindications and cautions

Answer 13

• Hepatotoxic – avoid in liver impairment
• Photosensitivity
• Dysphagia
• Mysasthenia gravia
• Contraindicated in children under 12yrs, pregnant or breast-feeding women (deposition in growing bone and teeth staining).

Question 14

Photosensitivity

Answer 14

Avoid exposure to sunlight or sunlamps

DD
- Doxycycline
- Demeclocycline

Question 15

Dysphagia

Answer 15

Tablets should be swallowed whole with plenty of fluid whilst sitting or standing

Question 16

Mysasthenia gravia

Answer 16

May increase muscle weakness in patients with myasthenia gravis and exacerbate systemic lupus erythematosus.

Question 17

Renal impairment

Answer 17

Avoid tetracyclines EXCEPT
- Doxycycline
- Minocycline

Question 18

Hepatic impairment

Answer 18

Hepatotoxic
Avoid or use with caution, ESPECIALLY with concomitant hepatotoxic drugs

Question 19

Counselling points

Answer 19

• Antacids and aluminium, calcium, iron, magnesium and zinc salts decrease the absorption of tetracyclines;
• milk also reduces the absorption of demeclocycline, oxytetracycline and tetracycline.
• Tetracycline tablets, doxycycline capsules, minocycline tablets or capsules should all be swallowed whole with plenty of fluid while sitting or standing.

Question 20

do not take milk, indigesition remedies or medicines containing iron or zinc 2 hours before or after taking this medicine

Answer 20

Apart from DLM (does like milk)
Doxy
Lyme
Mino

Question 21

Avoid milk

Answer 21

DOT
- Demeclocycline
- Oxytetracycline
- Tetracycline

Question 22

Oesophageal irritation

Answer 22

DMT
- Doxycycline (caps)
- Minocycline (caps/tabs)
- Tetracycline (tabs)
Swallow whole with plenty of fluid during meals whilst sitting or standing upright

Question 23

What gap is required between doxycycline and the typhoid vaccine

Answer 23

3 days