Main Uses of Klaricid UD

Klaricid UD is an extended-release formulation of clarithromycin, a macrolide antibiotic. It is primarily used to treat a variety of bacterial infections caused by susceptible microorganisms. Because it is a modified-release tablet, it allows for a steady release of the active ingredient over a 24-hour period, typically requiring once-daily administration.

Respiratory Tract Infections

The medication is frequently prescribed for infections affecting both the upper and lower respiratory tracts. This includes:

• Pharyngitis and Tonsillitis: Inflammation of the throat and tonsils caused by bacterial pathogens.
• Acute Maxillary Sinusitis: Infection of the sinus cavities.
• Acute Exacerbation of Chronic Bronchitis: Sudden worsening of symptoms in individuals with long-term bronchial inflammation.
• Community-Acquired Pneumonia: Lung infections developed outside of a hospital setting, ranging from mild to moderate severity.

Skin and Soft Tissue Infections

Klaricid UD is also indicated for uncomplicated infections of the skin and underlying soft tissues. These infections often manifest as redness, swelling, or localized pain and are typically caused by bacteria such as Staphylococcus aureus or Streptococcus pyogenes.

Benefits of Klaricid UD

Targeted Antibacterial Action

Clarithromycin works by inhibiting the protein synthesis of bacteria, effectively stopping their growth and allowing the body's immune system to clear the infection. It is effective against a broad spectrum of Gram-positive and some Gram-negative aerobic and anaerobic bacteria.

Sustained Release Profile

The "UD" (Ultra Dose or Unidie) designation refers to the extended-release technology. The primary benefit of this delivery system is the maintenance of consistent therapeutic levels of the medication in the bloodstream throughout the day. This delivery method is designed to provide effective treatment while minimizing the frequency of dosing compared to immediate-release formulations.

Regulatory References

1. Official FDA Prescribing Information

The official regulatory profile for Klaricid UD (Clarithromycin Extended-Release) defines its eligibility based on age, cardiac health, and organ function, strictly limiting its use.

Eligibility Scope

Classification	Population	Status Defined by Regulators
Allowed	Adults	Extended-release tablets are generally indicated only in this age group.
Not Recommended	Children under 12 years	Other formulations, like the oral suspension, are recommended.
Not Advised	Pregnant Women	Safety has not been established, and use is not advised unless the benefit justifies the risk.

Official Contraindications

Use is contraindicated (absolutely prohibited) in individuals with a known hypersensitivity to any macrolide antibiotic, including clarithromycin. Absolute non-eligibility also applies to patients with a history of QT prolongation or ventricular cardiac arrhythmia (including Torsades de Pointes).

Condition-Specific Restrictions

The extended-release formulation is contraindicated in patients with severe renal impairment (Creatinine Clearance <30 mL/min), as the 500 mg dose cannot be reduced as required. Use is also prohibited in patients suffering from severe hepatic failure in combination with renal impairment or those with uncorrected hypokalaemia or hypomagnesaemia.

Interactions with Other Medicines and Products

The interaction profile of Klaricid UD (Clarithromycin) is primarily defined by its documented activity as a strong inhibitor of the enzyme Cytochrome P450 3A4 (CYP3A4), which increases the systemic exposure of many co-administered substances.

Formally Contraindicated Combinations

Co-administration is officially prohibited by regulatory authorities with specific drugs due to severe interaction risks:

• Cardiac-risk Agents: Cisapride, Pimozide, Astemizole, and Terfenadine are contraindicated due to the documented risk of QT prolongation and life-threatening arrhythmias.
• Ergot Alkaloids: Ergotamine and Dihydroergotamine are contraindicated due to the risk of acute ergot toxicity, including vasospasm and ischemia.
• Statins: Lovastatin and Simvastatin are contraindicated due to the metabolic interaction leading to increased risk of rhabdomyolysis.

Clinically Significant Pharmacokinetic Interactions

Clarithromycin increases the plasma concentrations of many CYP3A4 substrates, including Theophylline, Digoxin, and Carbamazepine. Co-administration with Oral Anticoagulants (e.g., Warfarin) is officially documented as increasing the risk of serious hemorrhage and necessitates frequent monitoring of the International Normalized Ratio (INR).

Administration-Specific Requirements

The extended-release formulation requires administration with food to prevent a reduction in the drug's systemic exposure. Co-administration with Zidovudine must be separated by at least 2 hours to avoid a reduction in Zidovudine serum levels. Additionally, the contraindication for Colchicine is specifically restricted to patients with co-existing renal or hepatic impairment.

Targeted Inhibition of Bacterial Protein Synthesis

The drug's primary action is highly specific: it directly targets and binds to the 50S ribosomal subunit within susceptible bacteria. This molecular interaction acts as an inhibitor and physical block, disrupting the essential process of assembling new proteins and consequently disrupting the pathogen's capacity for growth and replication .

Physiological Consequence: Growth Arrest and Clearance

By preventing the bacteria from synthesizing the proteins necessary for cellular survival and division, the drug effectively initiates a state of bacteriostasis (growth arrest). This physiological consequence drastically reduces the actively multiplying pathogen load, and the resultant reduction in active pathogen replication facilitates the host's natural immune processes.

Active Metabolite and Mechanism Limitations

The drug's action is sustained and complemented by an active form produced in the body, 14-hydroxyclarithromycin, which works cooperatively using the same ribosomal binding mechanism. However, this mechanism is constrained by bacterial defenses, primarily through target-site modification (altering the ribosomal binding pocket) or by deploying efflux pumps that actively expel the drug from the cell.

How to Use Klaricid UD

Klaricid UD is the extended-release formulation of Clarithromycin, designed for simplified once-daily administration. The usage patterns for this medication follow specific protocols to ensure appropriate therapeutic use. The drug is administered exclusively via the oral route.

Official Dosing and Administration Protocol

The standard adult regimen for the approved indications is 1 gram (1000 mg) taken once daily, typically achieved by consuming two 500 mg extended-release tablets. The length of treatment is fixed, usually spanning 7 days or 14 days, depending on the specific infection being addressed.

Administration Requirement	Official Instruction	Rationale
Intake Condition	Must be taken with food	Necessary to promote optimal drug absorption.
Physical Handling	Tablet must be swallowed whole	Required to preserve the controlled extended-release profile.
Dose Adjustment	Must be reduced by 50% for patients with severe renal impairment (CLcr < 30 mL/min).	Required to adjust the regimen to the patient's physiological ability to clear the drug.

Procedural Context

It is an explicit procedural requirement that the extended-release tablet is not chewed, broken, or crushed under any circumstances, as this would compromise the release kinetics of the drug. If a scheduled daily dose is missed, standard instructions advise patients to take the dose as soon as possible, but never to take a double dose to compensate for the skipped one.

Research Evidence / Overview of Studies for Klaricid UD

Evidence for Use in Acute Bacterial Exacerbation of Chronic Bronchitis (ABECB)

Research exploring Klaricid UD (clarithromycin extended-release) in the context of acute worsening of chronic bronchitis has primarily involved short-term, randomized controlled trials (RCTs). These studies included adult patients experiencing periods of heightened respiratory symptoms. The main focus of these trials was on outcomes related to physical discomfort and physiological monitoring. Key measurements included the rate at which symptom resolution was recorded, known as the clinical outcome measures, and whether the targeted bacteria were monitored for change, known as the microbiological change measures. The research base is structured on consistent, high-level controlled trials, as reviewed by scientific bodies. However, follow-up durations were limited to the short-term, and the optimal research question regarding the best duration of therapy remains an area where research is ongoing.

Evidence for Use in Acute Maxillary Sinusitis

The evidence base for using Klaricid UD in acute bacterial sinus infections relies on controlled trials, often utilizing blinded designs to compare the extended-release formulation to other standard anti-infectives. Studies monitored outcomes related to physical discomfort and radiological change measures, which involve observing improvement on imaging after the course of treatment. The findings described in the RCTs were generally deemed to be of High-level quality in assessing how the drug was evaluated in comparison to established treatments. However, comparative evidence is lacking for a direct, long-term research study of the extended-release formulation against the generic immediate-release version.

Evidence in Special Populations and Uncertainties

The initial studies primarily monitored responses in generally healthy adult outpatients; therefore, the results apply only to the populations studied. Subgroup findings are uncertain for specific patient groups, such as those with extensive co-existing chronic conditions. The research provides context but not individual predictions, and certain areas of uncertainty are consistently noted across the evidence landscape. For example, the research does not determine whether an individual will respond similarly, as study results reflect the specific conditions under which they were conducted.

Key Studies & References

1. Clarithromycin Extended-Release Tablets, USP: Full Prescribing Information and Dosage/Administration
2. Community-Acquired Pneumonia Treatment Guidelines and Dosing Information (Macrolides in combination therapy)

Common questions about Klaricid UD (FAQ)

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Q: Which specific bacteria does Klaricid UD target?

According to official product information, Klaricid UD is indicated for infections caused by specific susceptible types of bacteria. These commonly include isolates such as Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae.

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Q: What are the most common side effects of Klaricid UD?

The official safety data from clinical trials identifies several adverse reactions as most frequent. These commonly reported issues include abdominal pain, diarrhea, nausea, vomiting, and a change in taste perception, known as taste perversion (dysgeusia).

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Q: How does severe renal impairment affect the dose of Klaricid UD?

Regulatory information states that the extended-release tablet (Klaricid UD) is contraindicated (prohibited for use) in patients who have severe renal impairment (a serious decrease in kidney function). This is because the standard dose of the extended-release tablet cannot be safely reduced to the level required for these patients.

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Q: If I get side effects, what should I do?

Official warnings and precautions indicate that immediate medical attention may be necessary if you experience symptoms like a severe allergic reaction (e.g., rash or swelling) or signs that your liver may be affected, such as jaundice (yellowing of the skin or eyes) or unusually dark urine.

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Q: Is Klaricid UD the same as the generic form, Clarithromycin?

Klaricid UD is the brand name for the extended-release (ER or XL) version of the active ingredient, Clarithromycin. While the active medicine is the same, the extended-release format is specifically designed for once-daily use and has its own distinct indications and dosing schedule.

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Q: What if I accidentally take too much Klaricid UD (overdose)?

Official documents on overdosage suggest that effects are expected to be intensified versions of the usual side effects. These typically involve the gastrointestinal system, and there may also be changes in mental status. Treatment for an overdose is generally expected to be supportive, meaning care may focus on managing the symptoms.

How to Store and Dispose of Klaricid UD?

The official storage conditions for Klaricid UD (clarithromycin extended-release tablets) require the medicine to be kept at controlled room temperature, specifically between 20°C and 25°C (68°F and 77°F), with permitted excursions up to 30°C.

Storage Requirements

The tablets must be stored in the original container and kept tightly closed to ensure protection from light and moisture. It is strictly required to keep the medicine out of the sight and reach of children, and the product must not be frozen.

Disposal

Any unused or expired Klaricid UD must be thrown away according to official regulatory guidelines for the safe disposal of unused medicines.