General

Question 1

Window periods

Answer 1

Chlamydia: from 2 weeks (after last sexual exposure)
Gonorrhoea: from 2 weeks.
HIV: from 45 days (6w)
Syphilis: from 3 months.
Hepatitis B: from 3 months.
Hepatitis C: from 3 months.

Question 2

Vaccines available and regimes // Types of testing, PCR, NAAT

Question 3

Advice for doxycycline

Answer 3

• Stay out of the sun / protect, even on cloudy days
• GI upset (nausea/diarrheoa)
• Oesophageal irritation - take with full glass of water during a meal
• Avoid in pregnancy/ breast feeding
• Avoid indigestion remedies and medicines containing iron or zinc [tetracyclines bind to divalent cations and so taking these will prevent abx absorption].
• TBA: Can enhance anticoagulant effects.

Question 4

Advice for metronidazole

Answer 4

• Can cause GI upset
• Do not drink alcohol during or for 48 hours after treatment - N+V, flushing, headache.

This is because the combination can cause a disulfiram-like reaction.

Question 5

Advice for macrolides: clarithromycin, erythromycin & azithromycin

Answer 5

Can be used 2nd line in chlamydia

no particular pt advice but for me:

• they inhibit P450 enzymes which increases concentration of drugs metabolised by CYP enzymes e.g. warfarin [so inc risk bleeding] and statins [inc risk myopathy].
• caution with QT

Question 6

Advice for quinolones (cipro/ moxifloxacin/ levofloxacin/ Ofloxacin)

Answer 6

Used in older men epididymo-orchitis

• GI upset
• lowers seizure threshold and can give hallucinations
• tendon rupture
• QT prolongation
• Ofloxacin - aortic dissection**

Question 7

Advice for cephalosporins and carbapenems (ceftriaxone, cefalexin, cefotaxime, meropenem)

Answer 7

Gonorrhoea treatment

• GI upset