Doxycycline

Doxycycline
Share the knowledge

Indications

  • Acne vulgaris : Start at 100 mg once daily or twice daily and decrease the dosage once control is obtained.
  • Papulopustular rosacea : 40 mg daily for 4–8 weeks(FDA approved) or 50–100 mg once or twice daily.
  • Steroid rosacea : 100 mg once or twice a day.
  • Ocular Rosacea :100 mg once or twice daily.
  • Perioral dermatitis : 40 mg once daily.
  • Hidradenitis suppurativa :100 mg twice daily may prevent disease activation.
  • Bullous pemphigoid :100 mg twice daily.
  • Hailey-Hailey disease :100 mg daily may be continued for at least 3 months to gain control.
  • Cutaneous sarcoidosis: 200 mg daily.
  • Confluent and reticulated papillomatosis: 100 mg twice a day.
  • Prurigo pigmentosa : 200 mg daily.
  • α1‐antitrypsin deficiency panniculitis: 200 mg twice daily for 3 months
  • Cold urticaria: 200 mg per day for 3 weeks.
  • Acute febrile neutrophilic dermatosis: 200 mg daily.
  • Erythema migrans :100 mg po BID for 14 days.
  • Mild bowel associated dermatosis arthritis syndrome : 100 mg once to twice daily,
  • Suspected MRSA infection :100 mg PO 2 times a day.
  • Rickettsial infections: 100 mg po or iv twice daily.
  • Early syphilis for penicillin-allergic patients :100 mg po BID for 14 days.
  • Late latent for penicillin-allergic patients :100 mg po BID for 28 days.
  • Lymphogranuloma venereum :100 mg po twice daily.
  • Granuloma inguinale : 100 mg po BID until all lesions completely healed (at least 3 weeks).
  • Anthrax.
  • Atypical mycobacterial infections.
  • Granuloma annulare: 100 mg daily.
  • Perforating dermatoses: 100 mg daily.

Dosage

  • Bacterial infection: 100 mg PO/IV bid.
  • Sub-antimicrobial dose : 20 mg PO bid.

Mechanism of action

  • Bacteriostatic agents that inhibit bacterial protein synthesis by targeting the 30S ribosomal subunit of both gram‐positive and gram‐negative bacteria.
  • Anti‐inflammatory : inhibition of MMPs function.

Side effects

COMMON: dyspepsia, nausea, vomiting, anorexia, diarrhea, stomatitis, candidiasis, discolored teeth (<8 years old), esophagitis,
phlebitis (IV), lightheadedness, dizziness, vertigo, ataxia, headache, tinnitus, drowsiness, photosensitivity.

RARE: pseudotumor cerebri (with isotretinoin), neutropenia, thrombocytopenia, hepatotoxicity, Jarisch-Herxheimer reaction (when treating Treponema pallidum), superinfection, pseudomembranous colitis, increased intracranial pressure (infants), skeletal retardation (infants).


Contraindications

  • Hypersensitivity to drug/class.
  • Pregnancy, children, impaired liver or renal function.

Interactions

  • Absorption is impaired by polyvalent cations such as calcium, aluminum, magnesium, iron, zinc, and bismuth.
  • Antacids, some laxatives, medications containing magnesium (e.g. quinapril), dietary supplements, and dairy products can inhibit absorption.
  • Antacids, H2 blockers, and proton pump inhibitors increase stomach pH and thereby decrease absorption.
  • Potential toxicity of digoxin, lithium and warfarin.
  • Barbiturates, phenytoin, and carbamazepine decrease the half-life of doxycycline.

Pregnancy &Lactation

  • Pregnancy category D.
  • Doxycycline is excreted in breast milk, potentially leading to staining of the deciduous teeth, enamel hypoplasia, and impaired skeletal growth in developing fetuses and nursing infant.

Precautions

  • Caution is warranted when prescribing doxycycline for patients with severe liver disease.
  • Not recommended for persons aged, 8 years to avoid tooth discoloration.
  • To decrease the likelihood of esophagitis, the pills should not be “dry swallowed” and should be taken at least half an hour prior to bedtime

Drug Info

  • Doxycycline, which is excreted primarily by the GI tract in bile and can be used in patients with renal failure.
  • The incidence of photosensitivity is low but increases with increasing dose levels.
  • Doxycycline may be taken with or without food, but it is preferred to be taken with food to avoid gastrointestinal upset.
  • Modifed‐release (subantimicrobial) preparations of doxycycline appear to minimize the development of antibiotic resistance without loss of anti‐inflammatory effect.

Share the knowledge
Leave a Reply 0