Minocycline vs Tetracycline

Based on "Antibiotic and Chemotherapy"
written by Roger G. Finch

Minocycline advantages over Tetracycline

Minocycline is better absorbed, more lipophilic, and better tolerated in terms of gastrointestinal complaints.
Some medical experts believe that minocycline is the most effective tetracycline antibiotic for inflammatory dermatoses of sebaceous glands.

Tetracycline advantages over Minocycline

Tetracycline is effective for the same dermatological conditions as minocycline, including acne, perioral dermatitis, rosacea. However, tetracycline is available at lower cost than minocycline.
Tetracycline is available in topical formulations.

Minocycline	Tetracycline
Brand names
Dynacin®, Minocin®	Sumycin®, Actisit®
Drug class
Tetracycline antibiotic
Dose formulations
• Tablets • Tablets, extended-release • Capsules • Suspension • Parenteral	• Capsules • Tablets • Topical solution, ointment, cream
Antimicrobial spectrum
Tetracyclines have generally the same broad antimicrobial spectrum of activity: • Gram-positive and gram-negative bacteria • Atypical pathogens
Mechanism of action
• Tetracyclines are bacteriostatic and work by inhibiting protein synthesis.
Half-life
• 11 to 22 hours	• 6 to 12 hours
Oral bioavailability
• 90-100%, almost complete bioavailability	• 75%
Metabolism, Elimination
• Minocycline is metabolized by liver to inactive metabolites. • Despite high hepatic excretion of minocycline, drug accumulation does not occur in patients with liver disease.	• Tetracycline is mainly eliminated by the kidneys via glomerular filtration.
Contraindications
• Hypersensitivity to any of tetracycline antibiotics
Pregnancy category
D

Minocycline vs. Tetracycline for acne

Clinical studies3-4 show that the effect of minocycline is not stronger than tetracycline, but the action is quicker and more sustained than that of tetracycline.

Minocycline may be effective for patients with tetracycline-recalcitrant acne vulgaris. It has much better antibacterial activity against both Staphylococci and Propionibacterium acnes and produces less resistance than tetracycline1-2.

Minocycline vs. Tetracycline for Urethritis

Minocycline and tetracycline are similarly effective in the treatment of non-gonococcal urethritis6.

In comparative study5 61 of 77 (79%) men treated with tetracycline and 53 of 68 (78%) men treated with minocycline were free from urethritis one to two weeks after completing treatment. Both agents were effective against C. trachomatis, but activity against U. urealyticum was weaker. Side effects (predominantly gastrointestinal) were noted in 14 (18%) men treated with tetracycline and eight (12%) men treated with minocycline.

References

1. Eady EA, Cove JH, Holland KT, Cunliffe WJ. Superior antibacterial action and reduced incidence of bacterial resistance in minocycline compared to tetracycline-treated acne patients. Br J Dermatol. 1990 Feb;122(2):233-44. PubMed
2. Eady EA, Jones CE, Gardner KJ, Taylor JP, Cove JH, Cunliffe WJ. Tetracycline-resistant propionibacteria from acne patients are sensitive to minocycline. Br J Dermatol. 1993 May;128(5):556-60.
3. Hubbell CG, Hobbs ER, Rist T, White JW Jr. Efficacy of minocycline compared with tetracycline in treatment of acne vulgaris. Arch Dermatol. 1982 Dec;118(12):989-92. PubMed
4. Samuelson JS. An accurate photographic method for grading acne: initial use in a double-blind clinical comparison of minocycline and tetracycline. J Am Acad Dermatol. 1985 Mar;12(3):461-7. PubMed
5. Oriel JD, Ridgway GL. Comparison of tetracycline and minocycline in the treatment of non-gonococcal urethritis. Br J Vener Dis. 1983 Aug;59(4):245-8 PubMed
6. Turnbull BC, Stringer HC, Meech RJ. Tetracycline and minocycline in the management of non-gonococcal urethritis: a comparison. N Z Med J. 1982 Jul 14;95(711):460-2.