[.
]
Action/Kinetics:
More slowly absorbed, and thus more persistent, than other tetracyclines. Preferred for clients with impaired renal function for treating infections outside the urinary tract. From 80% to 95% is bound to serum proteins.
t
1/2: 14.5-22 hr; 30%-40% excreted unchanged in urine.
Additional Uses:
Orally for uncomplicated gonococcal infections in adults (except anorectal infections in males); acute epididymo-orchitis caused by
Neisseria gonorrhoeae and
Chlamydia trachomatis; gonococcal arthritis-dermatitis syndrome; nongonococcal urethritis caused by
C. trachomatis and
Ureaplasma urealyticum. Prophylaxis of malaria due to
Plasmodium falciparum in short-term travelers ( < 4 months) to areas with chloroquine- or pyrimethamine-sulfadoxine-resistant strains.
Dental use. Atridox to reduce bacteria associated with periodontal disease. Periostat as an adjunct to scaling and root planing to promote attachment level gain and reduce pocket depth in adult periodontitis.
Contraindications:
Prophylaxis of malaria in pregnant individuals and in children less than 8 years old. Use during the last half of pregnancy and in children up to 8 years of age (tetracycline may cause permanent discoloration of the teeth). Lactation.
Special Concerns:
Safety for IV use in children less than 8 years of age has not been established.
Additional Drug Interactions:
-
Barbiturates, Carbamazepine, Phenytoin /
Effect of doxycycline by
liver breakdown
-
Methotrexate / Possible GI and hematologic toxicity after high doses of methotrexate
How Supplied:
Doxycycline calcium:
Syrup: 50 mg/5 mL.
Doxycyline hyclate:
Capsule: 20 mg, 50 mg, 100 mg;
Enteric Coated Capsule: 100 mg;
Gel: 10%;
Powder for injection: 100 mg;
Tablet: 100 mg.
Doxycycline monohydrate:
Capsule: 50 mg, 100 mg;
Powder for Reconstitution: 25 mg/5 mL
Dosage
?Capsules, Delayed-Release Capsules, Oral Suspension, Syrup, Tablets, IV
Infections.
Adult: First day, 100 mg q 12 hr;
maintenance: 100-200 mg/day, depending on severity of infection.
Children, over 8 years (45 kg or less): First day, 4.4 mg/kg in 1-2 doses;
then, 2.2-4.4 mg/kg/day in divided doses depending on severity of infection. Children over 45 kg should receive the adult dose.
Acute gonorrhea.
200 mg at once given PO;
then, 100 mg at bedtime on first day, followed by 100 mg b.i.d. for 3 days. Alternatively, 300 mg immediately followed in 1 hr with 300 mg.
Syphilis (primary/secondary).
300 mg/day in divided PO doses for 10 days.
C. trachomatis infections.
100 mg b.i.d. PO for minimum of 7 days.
Prophylaxis of ``traveler's diarrhea.''
100 mg/day given PO.
Prophylaxis of malaria.
Adults: 100 mg PO once daily;
children, over 8 years of age: 2 mg/kg/day up to 100 mg/day.
Adjunct to promote attachment and level gain and to reduce pocket depth in adult periodontitis.
20 mg b.i.d. following scaling and planing. May be used for up to 9 months. Do no exceed recommended dose.
?IV
Endometritis, parametritis, peritonitis, salpingitis.
100 mg b.i.d. with 2 g cefoxitin, IV, q.i.d. continued for at least 4 days or 2 days after improvement observed. This is followed by doxycycline, PO, 100 mg b.i.d. for 10-14 days of total therapy.
NOTE: The Centers for Disease Control have established treatment schedules for STDs.
?Gel, 10%
Reduce bacteria due to periodontal disease.
Apply to affected area; gel conforms to shape of the periodontal pocket and solidfies. It releases doxycycline for about 7 days.
