Skip to content
ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Oral tetracycline antibiotic (anti-acne / anti-rosacea)

Doxycycline 100mg (Acne / Rosacea)

Brand names: Efracea (40mg MR — rosacea), Vibramycin-D, Doxycycline (generic)

Used in: Pneumonia COPD

Doxycycline is a tetracycline antibiotic used for respiratory and atypical/zoonotic infections, malaria prophylaxis, and at lower doses for inflammatory acne and rosacea.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

It inhibits bacterial protein synthesis at the 30S ribosomal subunit (bacteriostatic); in acne it also has anti-inflammatory effects.

Prescribing in practice

  • Avoid in pregnancy and in children under 12 (dental staining and effects on developing bone).
  • It causes photosensitivity (advise sun protection) and oesophageal irritation — take it with plenty of water and stay upright.
  • Absorption is reduced by calcium, iron, antacids and dairy — separate their timing.

Monitoring

Short courses need no routine monitoring; for longer acne courses review response and adverse effects.

Counselling the patient

  • Take it with a full glass of water and stay upright; not just before lying down.
  • Use sun protection, as you may burn more easily.
  • Separate it from milk, antacids and iron supplements.

Evidence & guidelines

Used for respiratory and atypical infections and as an option for inflammatory acne/rosacea per NICE/PHE guidance.

Reference: NICE CG184 Acne Vulgaris; BAD Acne Guidelines 2021; BAD Rosacea Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Pathways