Dirithromycin
Dirithromycin (Dynabac)
Dirithromycin
(die- rih-throw- MY- sin)
Pregnancy Category: C Dynabac (Rx)

Classification: Antibiotic, macrolide

Action/Kinetics: Rapidly absorbed and converted during intestinal absorption to the active erythromycylamine. Distributed throughout the body, including the lungs, GI tract, skin, soft tissues, and GU tract. Erythromycylamine acts by binding to the 50S ribosomal subunits of microorganisms, resulting in inhibition of protein synthesis. t 1/2: 2-36 hr. From 81% to 97% of erythromycylamine is excreted in the feces via the bile.

Uses: Acute bacterial exacerbations of chronic bronchitis due to Haemophilus influenzae, Moraxella catarrhalis or Streptococcus pneumoniae. Secondary bacterial infections of acute bronchitis due to M. catarrhalis or S. pneumoniae. Community-acquired pneumonia due to Legionella pneumophila, Mycoplasma pneumoniae or S. pneumoniae. Pharyngitis or tonsillitis due to Streptococcus pyogenes. Uncomplicated infections of the skin and skin structures due to Staphylococcus aureus or S. pyogenes.

Contraindications: Hypersensitivity to erythromycin or any other macrolide antibiotic. Use in children less than 12 years of age. Use in clients with known, suspected, or potential bacteremias since serum levels of the drug are not high enough in the serum to be effective. Use for the empiric treatment of acute bacterial exacerbations of chronic or secondary bacterial infections of acute bronchitis or for empiric treatment of uncomplicated skin and skin structure infections.

Special Concerns: Although dirithromycin eradicates S. pyogenes from the nasopharynx, data are lacking as to its effectiveness in preventing rheumatic fever. Use with caution during lactation. Safety and efficacy have not been determined in children less than 12 years of age.

Side Effects: GI: Pseudomembranous colitis abdominal pain, nausea, diarrhea, vomiting, dyspepsia, GI disorder, flatulence, abnormal stools, constipation, dry mouth, gastritis, gastroenteritis, mouth ulceration, taste perversion, thirst, dysphagia. CNS: Headache, dizziness, vertigo, insomnia, anxiety, depression, nervousness, paresthesia, somnolence. CV: Palpitation, vasodilation, syncope. GU: Dysmenorrhea, urinary frequency, vaginal moniliasis, vaginitis. Dermatologic: Rash, pruritus, urticaria, sweating. Respiratory: Increased cough, dyspnea, hyperventilation. Miscellaneous: Nonspecific pain, asthenia, anorexia, dehydration, edema, epistaxis, eye disorder, fever, flu syndrome, hemoptysis, malaise, peripheral edema, allergic reaction amblyopia, myalgia, neck pain, tinnitus, tremor, thirst.

Laboratory Test Alterations: ALT, AST, alkaline phosphatase, potassium, serum CPK, bands, segs, basophils, eosinophils, platelet count, total bilirubin, creatinine, GGT, leukocyte count, lymphocytes, monocytes, phosphorus, uric acid, Ca, hematocrit, hemoglobin. Platelet count, albumin, chloride, hematocrit, hemoblobin, lymphocytes, segmented neutrophils, phosphorus, serum alkaline phosphatase, serum uric acid, total protein.

Overdose Management: Symptoms: N&V;, epigastric distress, diarrhea. Treatment: Treat symptoms.

Drug Interactions: Antacids / Slightly absorption of dirithromycin H ₂-Antagonists / Slightly absorption of dirithromycin Pimozide / Not to be used together due to possible sudden death Terfendine / Possible serious cardiac dysrhythmias

How Supplied: Enteric-coated tablet: 250 mg

Dosage
?Tablets, Enteric-Coated Acute bacterial exacerbations of chronic bronchitis. Secondary bacterial infection of acute bronchitis.
Adults and children over 12 years of age: 500 mg once a day for 7 days.
Community-acquired pneumonia.
Adults and children over 12 years of age: 500 mg once a day for 14 days.
Pharyngitis or tonsillitis.
Adults and children over 12 years of age: 500 mg once a day for 10 days.
Uncomplicated skin and skin structure infections.
Adults and children over 12 years of age: 500 mg once a day for 5-7 days.