What is the Difference Between Doxycycline and Minocycline?

🆚 Go to Comparative Table 🆚

Doxycycline and minocycline are both tetracycline antibiotics used to treat various infections, including acne. While they have similar efficacy in treating acne, there are some differences between the two drugs:

  1. Absorption: Minocycline is more rapidly and completely absorbed than doxycycline. Dairy or calcium-rich foods may affect doxycycline's absorption by 50 to 20%.
  2. Tissue Penetration: Minocycline achieves higher penetration into saliva and cerebrospinal fluid compared to doxycycline and tetracycline. Both drugs have good tissue penetration, but minocycline is five times more lipophilic than doxycycline.
  3. Adverse Reactions: Doxycycline may be associated with more gastrointestinal (GI) upset than minocycline. Common side effects of minocycline include numbness, tingling, prickling sensation on skin, stomach issues, headaches, dry mouth, swollen tongue, sore throat, muscle pain, mood changes, itching of the rectum or vagina, skin discoloration, changes in color of tears or urine, ringing in the ears, sensitivity to sunlight, hair loss, and in rare cases, autoimmune reactions. Common side effects of doxycycline include stomach issues (nausea, vomiting) and photosensitivity (exaggerated sunburn).
  4. Formulations: Minocycline is available as oral immediate-release capsules and tablets in 50 mg, 75 mg, and 100 mg strengths, as well as extended-release capsules and tablets. It is also available as a powder to be reconstituted for injection and as a topical treatment. Doxycycline is available in various forms, including tablets, capsules, and suspension.

Both drugs are effective in treating acne, but the choice between them depends on factors such as absorption, adverse reactions, and specific patient needs.

Comparative Table: Doxycycline vs Minocycline

Doxycycline and minocycline are both oral antibiotics belonging to the tetracycline class, and they are considered first-line treatments for moderate-to-severe acne. However, there are some differences between the two medications:

Characteristic Doxycycline Minocycline
Bioavailability 90% to 100% 90% to 100%
Time to Peak 1.5 to 4 hours 1.5 to 4 hours
Half-life 15 to 24 hours 11 to 22 hours
Protein Binding 82% - 93% 76%
Metabolism Liver Liver
Elimination Kidney: 20% to 30%; Feces: 70% to 80% Kidney: 10% to 13%; Feces: 19%
Tissue Penetration 5 times more lipophilic than tetracycline 5 times more lipophilic than doxycycline

In terms of adverse reactions, minocycline may be associated with more vestibular, autoimmune, hepatic, and hypersensitivity reactions than doxycycline. Additionally, minocycline is more likely to cause side effects such as fatigue, fever, skin rashes, photosensitivity, and vaginal candidiasis, while doxycycline is associated with fewer adverse events.