Minocycline

How it works

It inhibits bacterial protein synthesis by binding the 30S ribosomal subunit; in acne it both suppresses Cutibacterium acnes and has anti-inflammatory effects on the pilosebaceous unit.

Prescribing in practice

• Unlike other acne antibiotics it can cause a drug-induced lupus-like syndrome, irreversible blue-grey pigmentation of skin, mucosa and scars, and benign intracranial hypertension — stop it and reassess if a lupus-like illness, new pigmentation, or headache with visual disturbance develops, and do not combine it with oral retinoids (additive intracranial-hypertension risk).
• It is contraindicated in pregnancy and breastfeeding and in children under 12 years, because tetracyclines deposit in developing teeth and bone and cause permanent tooth discolouration.
• It can cause photosensitivity and, like other tetracyclines, hepatotoxicity; reserve it and review the need to continue, in line with local antimicrobial guidance.

Monitoring

No routine blood monitoring is needed for short courses, but reassess periodically on prolonged treatment and investigate promptly if features of lupus-like syndrome, hepatitis or raised intracranial pressure appear.

Counselling the patient

• Report a persistent headache (especially with blurred or double vision), joint pains with feeling unwell, or new darkening of the skin, gums or scars.
• Use sun protection, as your skin may burn more easily.
• Take it with a full glass of water and tell your prescriber if you might be pregnant.

Evidence & guidelines

An option for inflammatory acne, but UK acne guidance generally favours other tetracyclines (such as lymecycline or doxycycline) given minocycline's distinctive adverse-effect profile.