Sexual Health Drugs

Question 1

Doxycycline drug class and clinical indications?

C-ATHLETICS RUN THROUGH

Answer 1

Tetracycline
Chlamydial infections inc. PID

Other uses:
Acne vulgaris: esp where there are inflamed papules
Treatment of IECOPD by H. Influenza, atypical pneumonia by mycoplasma, Chlamydia psittaci, Coxiella Burnetti

Question 2

Doxycycline MOA

Elimination?

Answer 2

Inhibits bacterial protein synthesis- bacteriostatic and specifically bind to the 30s subunit
Has a broad spectrum cover

Excreted in bile/ faeces

Question 3

Doxycycline side effects?

Answer 3

N+V
Hypersensitivity reactions- approx 1% of people
Oesophageal irritation
Ulceration and dysphagia
Photosensitivity
Discolouration of tooth enamel if prescribed for children
ICHTN : rare se

Question 4

Doxycycline contraindications/ cautions

Answer 4

Will bind to teeth (tetra to teeth) and bones during foetal development so should not be prescribed during pregnancy/ breastfeeding/ children <12

Avoid in people with renal impairment: anti-anabolic effect= raised plasma urea

Question 5

Doxycycline interactions

Answer 5

Bind to divalent cations
Should not be given within 2 hours of Ca2+, antacids or iron as it will prevent absorption (no 2 for 2 ions)

Warfarin: can enhance anticoagulant effect

Question 6

Doxycycline: Route and dose

Answer 6

Available in oral prep only

For Child 12–17 years AND Adults
Initially 200 mg daily in 1–2 divided doses for 1 day, then maintenance 100 mg daily.

Question 7

Azithromycin drug class and clinical indications?

Answer 7

Synthetic macrolide

Treatment for mycoplasma genitalium after the first 7 day treatment with doxycycline
For pregnant/ breastfeeding women for treatment of Chlamydia
Non-gonococcal urethritis
Uncomplicated gonorrhoea

Other use:
Treatment of respiratory/ skin and soft tissue infections as an alternative to penicllin

Question 8

Azithromycin MOA

Azithromycin elimination

Answer 8

Inhibit bacterial protein synthesis- bacteriostatic- bind to the 50s subunit

Hepatic metabolism: Eliminated unchanged in the faeces via biliary excretion and transintestinal secretion

Question 9

Azithromycin SEs

Answer 9

N+V 
Vomiting 
Abdo pain and diarrhoea 
Allergy 
Antibiotic associated colitis

Question 10

Azithromycin contraindications/ cautions

Answer 10

Contraindicated in those with:
- Macrolide hypersensitivity

Caution:

• Severe hepatic impairment
• Dose reduction in renal impairment

Question 11

Azithromycin interactions

Answer 11

Should be prescribed with caution in patients taking other drugs that prolong QT interval or cause arrythmias e.g. amiodarone, anti-psychotics, quinine, quinolone antibiotics and SSRIs

Question 12

Azithromycin route and dose

Answer 12

Oral prep only

Uncomplicated genital chlamydial infections: non-gonococcal urethritis: child (12-17) and adult: 1g for 1 dose

Uncomplicated gonorrhoea (anogenital and haryngeal infection) : 2g for 1 dose