Doxycycline versus ...
Doxycycline vs Doryx
Regular doxycycline is dissolved and absorbed in the stomach. Doryx contains specially enteric-coated pellets of doxycycline that pass through the stomach and dissolve only after reaching the small intestine. This helps to reduce gastrointestinal irritation.
Doxycycline vs Minocycline
Adverse effects are less likely to occur with doxycycline 7. The majority of doxycycline complaints are gastrointestinal followed by photo-sensitivity. As for minocycline, vestibular dysregulation (vertigo, incoordination, lightheadedness), nausea, and vomiting are the most commonly reported adverse events.
Minocycline is active against some strains of staphylococci 11 and H. influenzae resistant to other tetracyclines (due to its ability to penetrate the cells sufficiently to reach inhibiting concentrations).
Generally, doxycycline and minocycline offer comparable efficacy in the treatment of acne.
While minocycline has been proven to be as effective as doxycycline for the quantitative reduction of inflammatory acne lesions, it is considered by some practitioners to produce a more rapid and sustained clinical improvement.
In the randomized, comparative, clinical study1, 50 patients with acne vulgaris received doxycycline (50 mg daily) or minocycline (100 mg daily) for 12 weeks. Cure or improvement was found in 78% of the patients in the doxycycline group compared to 82% in the minocycline group.
Pulmonary, wound infections
In comparative clinical study, in pneumococcal pulmonary infections the rates of favorable clinical response to doxycycline and minocycline were 73% and 76% respectively 5.
In infections caused by Bacteroides sp. (mainly infections of wounds), doxycycline or minocycline resulted in a 71% rate of favorable bacteriological responses 5.
Doxycycline is preferable for upper respiratory tract infections and atypical pneumonias 2.
According the pharmacokinetic studies the blood Cmax is higher for doxycycline, whereas the sputum Cmax is, on average, higher for minocycline because of the greater penetration of the latter. The eradication of Haemophilus influenzae was uncertain with both3.
Urethritis and cervicitis
Minocycline, 100 mg nightly, is as effective as doxycycline, 100 mg twice daily, each given for 7 days in the treatment of nongonococcal urethritis and mucopurulent cervicitis. Vomiting and gastrointestinal upset occur more frequently with doxycycline 8.
Doxycycline vs Tetracycline
The principal differences of doxycycline from tetracycline are the convenience of less frequent administration, high bioavailability, and better tolerance.
Both doxycycline and tetracycline are effective for Lyme disease (LD) associated with erythema migrans6. However, doxycycline is preferred to tetracycline, particularly in patients with early disseminated disease, because of improved microbiologic activity and higher cerebrospinal fluid concentrations. Additionally, doxycycline is effective for human granulocytic ehrlichiosis, which may occur simultaneously with early LD.
In comparative study the cure rate was 100% in the tetracycline group and 93.9% in the doxycycline group. The two groups did not differ significantly in terms of the interval required for defervescence or for the alleviation of symptoms. There were no relapses in either group. These data suggest that 3-day doxycycline is as effective as conventional 7-day tetracycline therapy for the cure of scrub typhus and the prevention of relapses 9.
Doxycycline vs Ofloxacin
Urethritis and cervicitis
Ofloxacin appears to be a highly effective and well-tolerated alternative to doxycycline in nongonococcal sexually transmitted disease 16.
Women with culture-proven cervical Chlamydia trachomatis were randomized to receive either ofloxacin (300 mg) or doxycycline (100 mg), twice daily for 7 days. All 56 women had negative cultures 5 to 9 days after treatment. Four weeks later, 26 (93%) of 28 ofloxacin-treated patients and all 22 (100%) doxycycline-treated patients were cured 14.
In a prospective randomized trial13 men with uncomplicated urethritis were randomized to receive 1 week of therapy with either doxycycline (100 mg twice daily) or ofloxacin (300 mg twice daily). 56 men received ofloxacin and 52 (93%) were clinically cured. 44 men (83%) of the 53 treated with doxycycline were cured. All 30 patients with gonorrhea who were treated with ofloxacin became culture-negative, as compared with 32 of 34 patients receiving doxycycline. In contrast, three of 18 patients with Chlamydia trachomatis were microbiologic failures after ofloxacin, while all 10 treated with doxycycline were cured. Complaints of both regimens were generally mild.
Lower respiratory tract infections
The efficacy and tolerance of ofloxacin and doxycycline were compared in patients with lower respiratory tract infections15. 88 patients were treated for exacerbations of chronic bronchitis and 131 for pneumonia. Clinical cure was achieved in 18 of 52 patients with bronchitis treated with ofloxacin. Improvement occurred in 29 and failure in 5. In the doxycycline-treated bronchitis group 11 of 36 patients were cured, 22 improved and 1 failure occurred. Of 62 patients with pneumonia who were administered ofloxacin, 34 were cured, 26 improved and treatment failed in 2. In the doxycycline-treated group of patients with pneumonia 39 of 69 were cured, 23 improved and 7 failed to respond.
Doxycycline vs Ciprofloxacin
Pelvic inflammatory disease
In comparative study 17, ciprofloxacin was successful in all nine patients with chlamydial or gonococcal PID and in six of seven with nonchlamydial nongonococcal PID. The overall success rate with ciprofloxacin was 94% (15 of 16). Doxycycline plus metronidazole regimen was successful in five of seven patients with chlamydial or gonococcal PID and in nine of 13 patients with nonchlamydial nongonococcal PID. Thus, the overall success rate was 70% (14 of 20).
Doxycycline is better than ciprofloxacin in the treatment of non-gonococcal urethritis4.
In a randomised study of men suffering from non-gonococcal urethritis, in ciprofloxacin group pyuria was absent in 30% of patients after completion of therapy. In the 100 mg doxycycline group pyuria was absent in 60% of patients. In the 200 mg doxycycline group pyuria was absent in 40% patients.
Doxycycline vs Roxithromycin
In the experimental open study, efficacy in the eradication of Chlamydia trachomatis was 91.7% in the roxitromycine group, and 92% in the doxycycline group. Roxitromycine shows an in vivo activity similar to doxycycline, and it is an alternative in those women in whom tetracyclines are contraindicated 10.
The results of the study suggest that roxithromycin and doxycycline have equivalent efficacy for acute exacerbations of chronic bronchitis, but that roxithromycin is better tolerated 12.
Published: March 31, 2008