Adverse Reactions in Clinical Trials of a bioequivalent form of doxycycline hyclate capsules: In clinical trials of adult patients with periodontal disease 213 patients received 20 mg BID over a 9 - 12 month period. The most frequent adverse reactions occurring in studies involving treatment with a bioequivalent form of doxycycline hyclate capsules or placebo are listed below:
Incidence (%) of Adverse Reactions in Clinical Trials of Doxycycline Hyclate Capsules, 20mg (Bioequivalent to Doxycycline Hyclate Tablets, 20mg) vs. Placebo
| Adverse Reaction | Doxycycline Hyclate Capsules 20 mg BID (n=213) |
Placebo (n=215) |
| Headache | 55 (26%) | 56 (26%) |
| Common Cold | 47 (22%) | 46 (21%) |
| Flu Symptoms | 24 (11%) | 40 (19%) |
| Tooth Ache | 14 (7%) | 28 (13%) |
| Periodontal Abscess | 8 (4%) | 21 (10%) |
| Tooth Disorder | 13 (6%) | 19 (9%) |
| Nausea | 17 (8%) | 12 (6%) |
| Sinusitis | 7 (3%) | 18 (8%) |
| Injury | 11 (5%) | 18 (8%) |
| Dyspepsia | 13 (6%) | 5 (2%) |
| Sore Throat | 11 (5%) | 13 (6%) |
| Joint Pain | 12 (6%) | 8 (4%) |
| Diarrhea | 12 (6%) | 8 (4%) |
| Sinus Congestion | 11 (5%) | 11 (5%) |
| Coughing | 9 (4%) | 11 (5%) |
| Sinus Headache | 8 (4%) | 8 (4%) |
| Rash | 8 (4%) | 6 (3%) |
| Back Pain | 7 (3%) | 8 (4%) |
| Back Ache | 4 (2%) | 9 (4%) |
| Menstrual Cramp | 9 (4%) | 5 (2%) |
| Acid Indigestion | 8 (4%) | 7 (3%) |
| Pain | 8 (4%) | 5 (2%) |
| Infection | 4 (2%) | 6 (3%) |
| Gum Pain | 1 (<1%) | 6 (3%) |
| Bronchitis | 7 (3%) | 5 (2%) |
| Muscle Pain | 2 (1%) | 6 (3%) |
Note: Percentages are based on total number of study participants in each treatment group.
Adverse Reactions for Tetracyclines: The following adverse reactions have been observed in patients receiving tetracyclines:
Gastrointestinal: anorexia, nausea, vomiting, diarrhea, glossitis, dysphagia, enterocolitis, and inflammatory lesions (with vaginal candidiasis) in the anogenital region. Hepatotoxicity has been reported rarely. Rare instances of esophagitis and esophageal ulcerations have been reported in patients receiving the capsule forms of the drugs in the tetracycline class. Most of these patients took medications immediately before going to bed. (See DOSAGE AND ADMINISTRATION Section).
Skin: maculopapular and erythematous rashes. Exfoliative dermatitis has been reported but is uncommon. Photosensitivity is discussed above. (See WARNINGS Section).
Renal toxicity: Rise in BUN has been reported and is apparently dose related. (See WARNINGS Section).
Hypersensitivity reactions: urticaria, angioneurotic edema, anaphylaxis, anaphylactoid purpura, serum sickness, pericarditis, and exacerbation of systemic lupus erythematosus.
Blood: Hemolytic anemia, thrombocytopenia, neutropenia, and eosinophilia have been reported.