Azithromycin for Dogs & Cats - 500-mg (1 tablet) - [Antibiotic]

Azithromycin is an antibiotic medication used to treat bacterial infections in dogs and cats. It is effective against a wide range of bacterial species, making it a versatile treatment option for various infections. Azithromycin works by inhibiting the growth of bacteria, thereby allowing the immune system to effectively eliminate the infection.

Key Benefits:

• Broad-spectrum antibiotic: Effective against a wide range of bacterial infections.
• Easy to administer: Available in tablet or liquid form for convenient dosing.
• Well-tolerated: Generally well-tolerated with minimal side effects in most animals.
• Veterinary-prescribed: Should be used under the guidance of a veterinarian for proper diagnosis and treatment.

Indications:

Azithromycin is indicated for the treatment of the following bacterial infections in dogs and cats:

• Respiratory tract infections: Including bronchitis, pneumonia, and sinusitis.
• Skin and soft tissue infections: Such as abscesses, wounds, and cellulitis.
• Otitis externa: Infections of the external ear canal.
• Urogenital tract infections: Including cystitis and pyelonephritis.
• Gastrointestinal infections: Such as enteritis and colitis.
• Dental infections: Including periodontal disease and gingivitis.

How it works:

Azithromycin is a type of antibiotic known as a macrolide. It works by inhibiting the growth of bacteria, thereby stopping the infection from spreading and allowing the immune system to effectively eliminate the bacteria. Azithromycin does this by binding to the bacterial ribosome, which is the cellular machinery responsible for protein synthesis in bacteria. By binding to the ribosome, azithromycin prevents the bacteria from producing essential proteins necessary for their survival and reproduction. This ultimately leads to the death of the bacteria and the resolution of the infection. Azithromycin is effective against a wide range of bacteria, including both gram-positive and gram-negative species.

Specifications:

• Brand: Azithromycin
• Type: Oral tablet, oral suspension
• Indicated for: Treatment of bacterial infections in dogs and cats
• Dosage Form: Tablet, suspension
• Available Strengths: Tablets: 50 mg, 100 mg, 250 mg; Suspension: 100 mg/5 ml, 200 mg/5 ml
• Administration: Administer orally, with or without food
• Packaging: Available in blister packs (tablets) or bottles (suspension)
• Storage: Store at room temperature, away from moisture and heat
• Manufacturer: Various generic manufacturers
• Prescription Required: Yes, prescription-only medication. Must be prescribed by a veterinarian.

View Azithromycin Drug Facts Sheet.

It is important to follow your Veterinarian's prescription instructions for your pet.

In dogs, the usual dosage is 2.5 to 5 mg per pound 5 to 10 mg/kg orally once daily for up to 7 days

In cats, the usual dosage is 2.5 to 7.5 mg per pound 5 to 15 mg/kg orally every 12 to 24 hours for up to 7 days

The duration of administration depends on the condition being treated, response to the medication and the development of any adverse effects.

Be certain to complete the prescription unless specifically directed by your veterinarian. Even if your pet feels better, the entire treatment plan should be completed to prevent relapse.

Dosing Informaton for Liquid:

Mixing Directions:

Tap Bottle to loosen powder. Add listed amount of water to the bottle. After mixing, use within 10 days. Discard after full dosing is completed. After mixing, store suspension at 41 to 86 degrees F. Oversized bottle provides extra space for shaking.

Shake Well Before Using.

Administration of Liquid:

For liquids, shake well before accurately measuring the dose. If using the suspension, give on empty stomach. Give medication as directed by your veterinarian. This medication is usually given once or twice daily. Read and follow the label carefully. Give the exact amount prescribed and only as often as directed. Missed doses reduce the effectiveness of therapy. Give this medication for as long as your veterinarian directs. Finish the entire course of treatment. Ideally, give the medication at the same time daily.

Precautions and Side Effects:

Azithromycin should not be used in animals with known hypersensitivity or allergy to it or other macrolide antibiotics. In addition, it should be used with great caution if at all when there is preexisting liver disease. Gastrointestinal side effects may include vomiting, diarrhea, or abdominal pain. Angioedema and cholestatic jaundice have been reported rarely in treated humans. Cardiac arrhythmias, including ventricular tachycardia, may be precipitated by azithromycin. Renal dysfunction, including interstitial nephritis and acute renal failure, may occur secondary to azithromycin treatment and liver function may be affected.

Drug Interactions:

Azithromycin may elevate serum digoxin levels. When ergotamine or dihydroergotamine are concurrently administered with azithromycin ergot toxicity may occur. Azithromycin causes a decrease in the clearance of triazolam and thus an increase in its pharmacologic effects Pimozide is contraindicated in patients receiving azithromycin, and vice versa death may result Animals being treated with cisapride should not be given azithromycin or other macrolide antibiotic Drugs metabolized by cytochrome P450 e.g. carbamazepine, terfenadine, cyclosporine, hexobarbital, and phenytoin will have their serum levels elevated by azithromycin Oral antacids reduce the absorption of azithromycin.

Indications and Usage

Azithromycin for injection is indicated for the treatment of patients with infections caused by susceptible strains of the designated microorganisms in the conditions listed below. As recommended dosages, durations of therapy, and applicable patient populations vary among these infections, please see Dosage and administration for dosing recommendations.

Community-acquired pneumonia due to Chlamydia pneumoniae, Haemophilus influenzae, Legionella pneumophila, Moraxella catarrhalis, Mycoplasma pneumoniae, Staphylococcus areus, or Streptococcus pneumoniae in patients who require initial intravenous therapy.

Pelvic inflammatory disease due to Chlamydia trachomatis, Neisseria gonorrhoeae, or Mycoplasma hominisin patients who require initial intravenous therapy. If anaerobic microorganisms are suspected of contributing to the infection, an antimicrobial agent with anaerobic activity should be administered in combination with azithromyzin for injection.

Azithromycin for injection should be followed by azithromycin by the oral route as required. (See Dosage and Administration.)

Appropriate culture and susceptibility tests should be performed before treatment to determine the causative microorganism and its susceptibility to azithromycin. Therapy with azithromycin may be initiated before results of these tests are known; once the results become available, antimicrobial therapy should be adjusted accordingly.

To reduce the development of drug-resistant bacteria and maintain the effectiveness of azithromycin and other antibacterial drugs, azithromycin should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

Contraindications

Azithromycin is contraindicated in patients with known hypersensitivity to azithromyzin, erythromycin, any macrolide or ketolide antibiotic.

Warnings

Serious allergic reactions, including angioedema, anaphylaxis, and dermatologic reactions including Stevens Johnson Syndrome and toxic epidermal nerolysis have been reported rarely in patients on azithromycin therapy. Although rare, fatalities have been reported. (See Contraindications.) Despite initially successful symptomatic treatment of the allergic symptoms, when symptomatic therapy was discontinued, the allergic symptoms recurred soon thereafter in some patients without further azithromycin exposure. These patients required prolonged periods of observation and symptomatic treatment. The relationship of these episodes to the long tissue half-life of azithromycin and subsequent prolonged exposure to antigen is unknown at present.

If an allergic reaction occurs, the drug should be discontinued and appropriate therapy should be instituted. Physicians should be aware that reappearance of the allergic symptoms may occur when symptomatic therapy is discontinued.

Clostridium diggicile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including azithromycin for injection, and may range in everity from mild diarrhea 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.

Precautions

General

Because azithromycin is principally eliminated via the liver, caution should be exercised when azithromycin is administered to patients with impaired hepatic function. Due to the limited data in subjects with GFR <10mL/min, caution should be exercised when prescribing azithromycin in these patients. (See Clinical Pharmacology, Special Populations, Renal Insufficiency.)

Azithromycin for injection should be reconstituted and diluted as directed and administered as an intravenous infusion over not less than 60 minutes. (See Dosage and Administration.)

Local I.V. site reactions have been reported with the intravenous administration of azithromycin. The incidence and severity of these reactions were the same when 500 mg azithromycin were given over 1 hour (2 mg/mL as 250 mL infusion) or over 3 hours (1 mg/mL infusion). (see adverse Reactions.) All volunteers who received infusate concentrations above 2 mg/mL experience local I.V. site reactions and, therefore, higher concentrations should be avoided.

Prolonged cardiac repolarization and QT interval, imparting a risk of developing cardiac arrhythmia and torsades de pointes, have been seen in treatment with other macrolides. A similar effect with azithromycin cannot be completely ruled out in patients at increased risk for prolonged cardiac repolarization.

Exacerbation of symptoms of myasthenia gravis and new onset of myasthenic syndrome have been reported in patients receiving azithromycin therapy.

Prescribing azithromycin in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.

Information for Patients

Patients should be directed to discontinue azithromycin and contact a physician if any signs of an allergic reaction occur.

Patients should be counseled that antibacterial drugs including azithromycin should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When azithromycin is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of the therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may decrease the effectiveness of the immediate treatment and increase the likelihood that bacteria will develop resistance and will not be treatable by azithromycin or other antibacterial drugs in the future.

Diarrhea is a common problem caused by antibiotics which usually ends when the antibiotic is discontinued. Sometimes after starting treatment with antibiotics, patients can develop watery and bloody stools (with or without stomach cramps and fever) even as late as two or more months after having taken the last dose of the antibiotic, If this occurs, patients should contact their physician as soon as possible.

Adverse Reactions

In clinical trials of intravenous azithromycin for community-acquired pneumonia, in which 2 to 5 I.V. doses were given, most of the reported side effects were mild to moderate in severity and were reversible upon discontinuation of the drug. The majority of patients in these trials had one or more comorbid diseases and were receiving concomitant medications. Approximately 1.2% of the patients discontinued intravenous azithromycin therapy, and a total of 2.4% discontinued azithromycin therapy by either the intravenous or oral route because of clinical or laboratory side effects.

In clinical trials conducted in patients with pelvic inflammatory disease, in which 1 to 2 I.V. doses were given, 2% of women who received monotherapy with azithromycin plus metronidazole discontinued therapy due to clinical side effects.

Clinical side effects leading to discontinuations from these studies were most commonly gastrointestinal (abdominal pain, nausea, vomiting, diarrhea), and rashes; laboratory side effects leading to discontinuation were increases in transaminase levels and/or alkaline phosphatase levels.

Clinical

Overall, the most common side effects associated with treatment in adult patients who received I.V./P.O. azithromycin in studied of community-acquired pneumonia were related to the gastrointestinal system with diarrhea/loose stools (4.3%), nausea (3.9%), abdominal pain (2.7%), and vomiting (1.4% being the most frequently reported. Approximately 12% of patients experienced a side effect related to the intravenous infusion; most common were pain at the injection site (6.5% and local inflammation (3.1%).

The most common side effects associated with treatment in adult women who received I.V./P.O. azithromycin in studies of pelvic inflammatory disease were related to the gastrointestinal system. Diarrhea (8.5%) and nausea (6.6%) were most commonly reported, followed by vaginitis (2.8%), abdominal pain (1.9%), anorexia (1.9%), rash and pruritus (1.9%). When azithromycin was co-administered with metronidazole in these studies, a higher proportion of women experienced side effects of nausea (10.3%), abdominal pain (3.7%), vomiting (2.8%), application site reaction, stomatitis, dizziness, or dyspnea (all at 1.9%).

No other side effects occurred in patients on the multiple dose I.V./P.O. regimen of azithromycin in these studies with a frequency greater than 1%.

Side effects that occurred with a frequency of 1% or less included the following:

Gastrointestinal: dyspepsia, flatulence, mucositis, oral moniliasis, and gastritis

Nervous System: headache, somnolence

Allergic: bronchospasm

Special Senses: taste perversion

Post-Marketing Experience

Adverse events reported with azithromycin during the post-marketing period in adult and/or pediatric patients for which a causal relationship may not be established include:

Allergic: Arthralgia, edema, urticaria and angioedema

Cardiovascular: Arrhythmias including ventricular tachycardia and hypotension. There have been rare reports of QT prolongation and torsades de pointes.

Gastrointestinal: Anorexia, constipation, dyspepsia, flatulence, vomiting/diarrhea rarely resulting in dehydration, pseudomembranous colitis, pancreatitis, oral candidiasis and rare reports of tongue discoloration.

General: Asthenia, paresthesia, fatigue, malaise and anaphylaxis (rarely fatal).

Genitourinary: Interstitial nephritis and acute renal failure and vaginitis.

Hematopoietic: Thrombocytopenia.

Liver/Biliary: Abnormal liver function including hepatitis and cholestatic jaundice, as well as rare cases of hepatic necrosis and hepatic failure, some of which have resulted in death.

Nervous System: Convulsions, dizziness/vertigo, headache, somnolence, hyperactivity, nervousness, agitation and syncope.

Psychiatric: Aggressive reaction and anxiety.

Skin/Appendages: Pruritus, rarely serious skin reactions including erythema multiforme, Stevens Johnson Syndrome and toxic epidermal necrolysis.

Special Senses: Hearing disturbances including hearing loss, deafness and/or tinnitus and rare reports of taste/smell perversion and/or loss.

Storage:

When diluted according to the instructions (1 mg/mL to 2 mg/mL), azithromycin for injection is stable for 24 hours at or below room temperature (30°C or 86°F), or for 7 days if stored under refrigeration (5°C or 41°F).