FDA Label for Doxycycline

1 Indications And Usage

1.1 Indication

Doxycycline 40 mg is indicated for the treatment of only inflammatory lesions (papules and pustules) of rosacea in adult patients. No meaningful effect was demonstrated for generalized erythema (redness) of rosacea.

1.2 Limitations Of Use

This formulation of doxycycline has not been evaluated in the treatment or prevention of infections. Doxycycline 40 mg should not be used for treating bacterial infections, providing antibacterial prophylaxis, or reducing the numbers or eliminating microorganisms associated with any bacterial disease.

To reduce the development of drug-resistant bacteria as well as to maintain the effectiveness of other antibacterial drugs, Doxycycline 40 mg should be used only as indicated.

Efficacy of Doxycycline 40 mg beyond 16 weeks and safety beyond 9 months have not been established.

Doxycycline 40 mg has not been evaluated for the treatment of the erythematous, telangiectatic, or ocular components of rosacea.

2 Dosage And Administration

2.1 General Dosing Information

One Doxycycline Capsule (40 mg) should be taken once daily in the morning on an empty stomach, preferably at least one hour prior to or two hours after meals.

Administration of adequate amounts of fluid along with the capsules is recommended to wash down the capsule to reduce the risk of esophageal irritation and ulceration [see Adverse Reactions (6)].

2.2 Important Considerations For Dosing Regimen

The dosage of Doxycycline 40 mg differs from that of doxycycline used to treat infections. Exceeding the recommended dosage may result in an increased incidence of side effects including the development of resistant organisms.

3 Dosage Forms And Strengths

40 mg beige opaque capsule imprinted with “GLD 40”

4 Contraindications

This drug is contraindicated in persons who have shown hypersensitivity to doxycycline or any of the other tetracyclines.

5 Warnings And Precautions

5.1 Teratogenic Effects

Doxycycline 40 mg should not be used during pregnancy.

Doxycycline, like other tetracycline-class antibiotics, can cause fetal harm when administered to a pregnant woman. If any tetracycline is used during pregnancy or if the patient becomes pregnant while taking these drugs, the patient should be informed of the potential hazard to the fetus and treatment stopped immediately.

The use of drugs of the tetracycline-class during tooth development (last half of pregnancy, infancy, and childhood up to the age of 8 years) may cause permanent discoloration of the teeth (yellow-gray-brown). This adverse reaction is more common during long-term use of the drug but has been observed following repeated short-term courses. Enamel hypoplasia has also been reported. Tetracycline drugs, therefore, should not be used during tooth development unless other drugs are not likely to be effective or are contraindicated.

All tetracyclines form a stable calcium complex in any bone-forming tissue. A decrease in fibula growth rate has been observed in premature human infants given oral tetracycline in doses of 25 mg/kg every 6 hours. This reaction was shown to be reversible when the drug was discontinued.

Results of animal studies indicate that tetracyclines cross the placenta, are found in fetal tissues, and can cause retardation of skeletal development on the developing fetus. Evidence of embryotoxicity has been noted in animals treated early in pregnancy.

5.2 Pseudomembranous Colitis

Clostridium difficile associated diarrhea (CDAD) has been reported with nearly all antibacterial agents, including doxycycline, and may range in severity from mild to fatal colitis.

Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile.

C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents.

If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile, and surgical evaluation should be instituted as clinically indicated.

5.3 Metabolic Effects

The anti-anabolic action of the tetracyclines may cause an increase in BUN. While this is not a problem in those with normal renal function, in patients with significantly impaired function, higher serum levels of tetracycline-class antibiotics may lead to azotemia, hyperphosphatemia, and acidosis. If renal impairment exists, even usual oral or parenteral doses may lead to excessive systemic accumulations of the drug and possible liver toxicity. Under such conditions, lower than usual total doses are indicated, and if therapy is prolonged, serum level determinations of the drug may be advisable.

5.4 Photosensitivity

Photosensitivity manifested by an exaggerated sunburn reaction has been observed in some individuals taking tetracyclines. Although this was not observed during the duration of the clinical studies with Doxycycline 40 mg, patients should minimize or avoid exposure to natural or artificial sunlight (tanning beds or UVA/B treatment) while using Doxycycline 40 mg. If patients need to be outdoors while using Doxycycline 40 mg, they should wear loose-fitting clothes that protect skin from sun exposure and discuss other sun protection measures with their physician.

5.5 Autoimmune Syndromes

Tetracyclines have been associated with the development of autoimmune syndromes. Symptoms may be manifested by fever, rash, arthralgia, and malaise. In symptomatic patients, liver function tests, ANA, CBC, and other appropriate tests should be performed to evaluate the patients. Use of all tetracycline-class drugs should be discontinued immediately.

5.6 Tissue Hyperpigmentation

Tetracycline-class drugs are known to cause hyperpigmentation. Tetracycline therapy may induce hyperpigmentation in many organs, including nails, bone, skin, eyes, thyroid, visceral tissue, oral cavity (teeth, mucosa, alveolar bone), sclerae and heart valves. Skin and oral pigmentation has been reported to occur independently of time or amount of drug administration, whereas other pigmentation has been reported to occur upon prolonged administration. Skin pigmentation includes diffuse pigmentation as well as over sites of scars or injury.

5.7 Pseudotumor Cerebri

Pseudotumor cerebri (benign intracranial hypertension) in adults has been associated with the use of tetracyclines. The usual clinical manifestations are headache and blurred vision. Bulging fontanels have been associated with the use of tetracyclines in infants. While both of these conditions and related symptoms usually resolve after discontinuation of the tetracycline, the possibility for permanent sequelae exists. Patients should be questioned for visual disturbances prior to initiation of treatment with tetracyclines and should be routinely checked for papiledema while on treatment.

5.8 Development Of Drug Resistant Bacteria

Bacterial resistance to tetracyclines may develop in patients using Doxycycline 40 mg. Because of the potential for drug-resistant bacteria to develop during the use of Doxycycline 40 mg, it should only be used as indicated.

5.9 Superinfection

As with other antibiotic preparations, use of Doxycycline 40 mg may result in over-growth of non-susceptible microorganisms, including fungi. If superinfection occurs, Doxycycline 40 mg should be discontinued and appropriate therapy instituted. Although not observed in clinical trials with Doxycycline 40 mg, the use of tetracyclines may increase the incidence of vaginal candidiasis. Doxycycline 40 mg should be used with caution in patients with a history of or predisposition to Candida overgrowth.

5.10 Laboratory Monitoring

Periodic laboratory evaluations of organ systems, including hematopoietic, renal and hepatic studies should be performed. Appropriate tests for autoimmune syndromes should be performed as indicated.

6 Adverse Reactions

6.1 Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Adverse Reactions in Clinical Trials of Doxycycline 40 mg: In controlled clinical trials of adult subjects with mild to moderate rosacea, 537 subjects received Doxycycline 40 mg or placebo over a 16-week period. The following table summarizes selected adverse reactions that occurred in the clinical trials at a rate of ≥1% for the active arm:

Note: Percentages 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 at higher, antimicrobial doses:

Gastrointestinal: anorexia, nausea, vomiting, diarrhea, glossitis, dysphagia, enterocolitis, and inflammatoy 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 the patients experiencing esophagitis and/or esophageal ulceration took their medication immediately before lying down [see Dosage and Administration (2)].

Skin: maculopapular and erythematous rashes. Exfoliative dermatitis has been reported but is uncommon. Photosensitivity is discussed above [see Warnings and Precautions (5.4)].

Renal toxicity: Rise in BUN has been reported and is apparently dose-related [see Warnings and Precautions (5.3)].

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.

6.2 Postmarketing Experience

Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. The following adverse reactions have been identified during post approval use of Doxycycline 40 mg:

• Nervous system: Pseudotumor cerebri (benign intracranial hypertension), headache.

7 Drug Interactions

7.1 Anticoagulants

Because tetracyclines have been shown to depress plasma prothrombin activity, patients who are on anticoagulant therapy may require downward adjustment of their anticoagulant dosage.

7.2 Penicillin

Since bacteriostatic drugs may interfere with the bactericidal action of penicillin, it is advisable to avoid giving tetracycline-class drugs in conjunction with penicillin.

7.3 Methoxyflurane

The concurrent use of tetracycline and methoxyflurane has been reported to result in fatal renal toxicity.

7.4 Antacids And Iron Preparations

Absorption of tetracyclines is impaired by bismuth subsalicylate, proton pump inhibitors, antacids containing aluminum, calcium or magnesium and iron-containing preparations.

7.5 Low Dose Oral Contraceptives

Doxycycline may interfere with the effectiveness of low dose oral contraceptives. To avoid contraceptive failure, females are advised to use a second form of contraceptive during treatment with doxycycline.

7.6 Oral Retinoids

There have been reports of pseudotumor cerebri (benign intracranial hypertension) associated with the concomitant use of isotretinoin and tetracyclines. Since both oral retinoids, including isotretinoin and acitretin, and the tetracyclines, primarily minocycline, can cause increased intracranial pressure, the concurrent use of an oral retinoid and a tetracycline should be avoided.

7.7 Barbiturates And Anti-Epileptics

Barbiturates, carbamazepine, and phenytoin decrease the half-life of doxycycline.

7.8 Drug/Laboratory Test Interactions

False elevations of urinary catecholamine levels may occur due to interference with the fluorescence test.

8 Use In Specific Populations

8.1 Pregnancy

Teratogenic Effects: Pregnancy Category D [see Warnings and Precautions (5.1)]. Results from animal studies indicate that doxycycline crosses the placenta and is found in fetal tissues.

8.3 Nursing Mothers

Tetracyclines are excreted in human milk. Because of the potential for serious adverse reactions in infants from doxycycline, Doxycycline 40 mg should not be used in mothers who breastfeed.

8.4 Pediatric Use

Doxycycline 40 mg should not be used in infants and children less than 8 years of age [see Warnings and Precautions (5.1)]. Doxycycline 40 mg has not been studied in children of any age with regard to safety or efficacy, therefore use in children is not recommended.

8.5 Geriatric Use

Clinical studies of Doxycycline 40 mg did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and concomitant disease or other drug therapy.

10 Overdosage

In case of overdosage, discontinue medication, treat symptomatically, and institute supportive measures. Dialysis does not alter serum half-life and thus would not be of benefit in treating cases of overdose.

11 Description

Doxycycline, USP Capsules 40 mg are hard gelatin capsule shells filled with two types of doxycycline beads (30 mg immediate release and 10 mg delayed release) that together provide a dose of 40 mg of anhydrous doxycycline (C₂₂H₂₄N₂O₈). The structural formula of doxycycline, USP is:

chem-struct - chem struct

with an empirical formula of C₂₂H₂₄N₂O₈•H₂O and a molecular weight of 462.46. The chemical designation for doxycycline is 2-Naphthacenecarboxamide,4-(dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro- 3,5,10,12,12a-pentahydroxy-6-methyl-1,11-dioxo-, [4S-(4α, 4aα, 5α, 5aα, 6α,12aα)]-, monohydrate. It is very slightly soluble in water.

Inert ingredients in the formulation are: hypromellose, iron oxide red, iron oxide yellow, methacrylic acid copolymer, polyethylene glycol, Polysorbate 80, sugar spheres, talc, titanium dioxide, and triethyl citrate. Active ingredients: Each capsule contains doxycycline, USP in an amount equivalent to 40 mg of anhydrous doxycycline.

12 Clinical Pharmacology

12.1 Mechanism Of Action

The mechanism of action of Doxycycline 40 mg in the treatment of inflammatory lesions of rosacea is unknown.

12.3 Pharmacokinetics

Doxycycline 40 mg capsules are not bioequivalent to other doxycycline products. The pharmacokinetics of doxycycline following oral administration of Doxycycline 40 mg was investigated in 2 volunteer studies involving 61 adults.

Pharmacokinetic parameters for Doxycycline 40 mg following single oral doses and at steady-state in healthy subjects are presented in Table 2.

Absorption: In a single-dose food-effect study involving administration of Doxycycline 40 mg to healthy volunteers, concomitant administration with a 1000 calorie, high-fat, high-protein meal that included dairy products, resulted in a decrease in the rate and extent of absorption (C_max and AUC) by about 45% and 22%, respectively, compared to dosing under fasted conditions. This decrease in systemic exposure can be clinically significant, and therefore if Doxycycline 40 mg is taken close to meal times, it is recommended that it be taken at least one hour prior to or two hours after meals.

Distribution: Doxycycline is greater than 90% bound to plasma proteins.

Metabolism: Major metabolites of doxycycline have not been identified. However, enzyme inducers such as barbiturates, carbamazepine, and phenytoin decrease the half-life of doxycycline.

Excretion: Doxycycline is excreted in the urine and feces as unchanged drug. It is reported that between 29% and 55.4% of an administered dose can be accounted for in the urine by 72 hours. Terminal half-life averaged 21.2 hours in subjects receiving a single dose of Doxycycline 40 mg.

Special Populations

Geriatric: Doxycycline pharmacokinetics have not been evaluated in geriatric patients.

Pediatric: Doxycycline pharmacokinetics have not been evaluated in pediatric patients [see Warnings and Precautions (5.1)].

Gender: The pharmacokinetics of Doxycycline 40 mg were compared in 16 male and 14 female subjects under fed and fasted conditions. While female subjects had a higher C_max and AUC than male subjects, these differences were thought to be due to differences in body weight/lean body mass.

Race: Differences in doxycycline pharmacokinetics among racial groups have not been evaluated.

Renal Insufficiency: Studies have shown no significant difference in serum half-life of doxycycline in patients with normal and severely impaired renal function. Hemodialysis does not alter the serum half-life of doxycycline.

Hepatic Insufficiency: Doxycycline pharmacokinetics have not been evaluated in patients with hepatic insufficieny.

Gastric Insufficiency: In a study in healthy volunteers (N=24) the bioavailability of doxycycline is reported to be reduced at high pH. This reduced bioavailability may be clinically significant in patients with gastrectomy, gastric bypass surgery or who are otherwise deemed achlorhydric.

Drug Interactions: [see Drug Interactions (7)].

12.4 Microbiology

Doxycycline is a member of the tetracycline-class of drugs. The plasma concentrations of doxycycline achieved with Doxycycline 40 mg during administration [see Clinical Pharmacology (12.3) and Dosage and Administration (2.2)] are less than the concentration required to treat bacterial diseases. Doxycycline 40 mg should not be used for treating bacterial infections, providing antibacterial prophylaxis, or reducing the numbers or eliminating microorganisms associated with any bacterial disease [see Indications and Usage (1.2)]. In vivo microbiological studies utilizing a similar drug exposure for up to 18 months demonstrated no detectable long term effects on bacterial flora of the oral cavity, skin, intestinal tract and vagina.

13 Nonclinical Toxicology

13.1 Carcinogenesis, Mutagenesis, Impairment Of Fertility

Doxycycline was assessed for potential to induce carcinogenesis in a study in which the compound was administered to Sprague-Dawley rats by gavage at dosages of 20, 75, and 200 mg/kg/day for two years. An increased incidence of uterine polyps was observed in female rats that received 200 mg/kg/day, a dosage that resulted in a systemic exposure to doxycycline approximately 12.2 times that observed in female humans who use Doxycycline 40 mg [exposure comparison based upon area under the curve (AUC) values]. No impact upon tumor incidence was observed in male rats up to 200 mg/kg/day, or in females at the lower dosages studied.

Doxycycline was assessed for potential to induce carcinogenesis in CD-1 mice by gavage at dosages 20, 75, and 150 mg/kg/day in males and at dosages of 20, 100, and 300 mg/kg/day in females. No impact upon tumor incidence was observed in male and female mice at systemic exposures approximately 4.2 and 8.3 times that observed in humans, respectively.

Doxycycline demonstrated no potential to cause genetic toxicity in an in vitro point mutation study with mammalian cells (CHO/HGPRT forward mutation assay) or in an in vivo micronucleus assay conducted in CD-1 mice. However, data from an in vitro mammalian chromosomal aberration assay conducted with CHO cells suggest that doxycycline is a weak clastogen. Oral administration of doxycycline to male and female Sprague-Dawley rats adversely affected fertility and reproductive performance, as evidenced by increased time for mating to occur, reduced sperm motility, velocity, and concentration, abnormal sperm morphology, and increased pre-and post-implantation losses. Doxycycline induced reproductive toxicity at all dosages that were examined in this study, as even the lowest dosage tested (50 mg/kg/day) induced a statistically significant eduction in sperm velocity. Note that 50 mg/kg/day is approximately 3.6 times the amount of doxycycline contained in the recommended daily dose of Doxycycline 40 mg when compared on the basis of AUC estimates. Although doxycycline impairs the fertility of rats when administered at sufficient dosage, the effect of Doxycycline 40 mg on human fertility is unknown.

14 Clinical Studies

The safety and efficacy of Doxycycline 40 mg in the treatment of only inflammatory lesions (papules and pustules) of rosacea was evaluated in two randomized, placebo-controlled, multi-centered, double-blind, 16-week Phase 3 trials involving 537 subjects (total of 269 subjects on Doxycycline 40 mg from the two trials) with rosacea (10 to 40 papules and pustules and two or fewer nodules). Pregnant and nursing women, subjects <18 years of age, and subjects with ocular rosacea and/or blepharitis/meibomianitis who require ophthalmologic treatment were excluded from trial. Mean baseline lesion counts were 20 and 21 for Doxycycline 40 mg and placebo subject groups respectively.

At Week 16, subjects in the Doxycycline 40 mg group were evaluated using co-primary endpoints of mean reduction in lesion counts and a dichotomized static Investigator’s Global Assessment of Clear or Almost Clear (defined as 1 to 2 small papules or pustules) when compared to the placebo group in both Phase 3 trials.

Subjects treated with Doxycycline 40 mg did not demonstrate significant improvement in erythema when compared to those treated with placebo.

16 How Supplied/Storage And Handling

Doxycycline 40 mg (beige opaque capsule imprinted with “GLD 40”) containing doxycycline, USP in an amount equivalent to 40 mg of anhydrous doxycycline.

Bottle of 30 (NDC 66993-815-30).

Storage:

All products are to be stored at controlled room temperatures of 15°C - 30°C (59°F - 86°F) and dispensed in tight, light-resistant containers (USP).

Keep out of reach of children.

17 Patient Counseling Information

See FDA-approved patient labeling (Patient Information)

Patients taking Doxycycline capsules 40 mg should receive the following information and instructions:

• It is recommended that Doxycycline 40 mg not be used by individuals of either gender who are attempting to conceive a child.
• It is recommended that Doxycycline 40 mg not be used by pregnant or breast feeding women.
• Patients should be advised that pseudomembranous colitis can occur with doxycycline therapy. If patients develop watery or bloody stools, they should seek medical attention.
• Patients should be advised that pseudotumor cerebri can occur with doxycycline therapy. If patients experience headache or blurred vision they should seek medical attention.
• Photosensitivity manifested by an exaggerated sunburn reaction has been observed in some individuals taking tetracyclines, including doxycycline. Patients should minimize or avoid exposure to natural or artificial sunlight (tanning beds or UA/B treatment) while using doxycycline. If patients need to be outdoors while using doxycycline, they should wear loose-fitting clothes that protect skin from sun exposure and discuss other sun protection measures with their physician. Treatment should be discontinued at the first evidence of sunburn.
• Concurrent use of doxycycline may render oral contraceptives less effective.
• Autoimmune syndromes, including drug-induced lupus-like syndrome, autoimmune hepatitis, vasculitis and serum sickness have been observed with tetracycline-class drugs, including doxycycline. Symptoms may be manifested by arthralgia, fever, rash and malaise. Patients who experience such symptoms should be cautioned to stop the drug immediately and seek medical help.
• Patients should be counseled about discoloration of skin, scars, teeth or gums that can arise from doxycycline therapy.
• Take Doxycycline 40 mg exactly as directed. Increasing doses beyond 40 mg every morning may increase the likelihood that bacteria will develop resistance and will not be treatable by other antibacterial drugs in the future.