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Quadtab

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Quadtab

Quadtab_EN

Method of action: Anti-Tuberculosis

Treatment option:

Medically reviewed

Marina Burgos

Last updated on 10/01/2026

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Quadtab

Quick Facts

Property Description
Active Ingredients Ethambutol, Isoniazid, Rifampicin, Pyrethrins
Form Fixed-Dose Combination (FDC) Tablet and Topical Preparation
Pharmacological Class Antitubercular (Antimycobacterial) and Anti-parasitic
Origin Synthetic, Semi-synthetic, and Naturally-derived components

What is Quadtab and What Type of Medicine is it?

Quadtab is defined as a specialized Fixed-Dose Combination (FDC) pharmaceutical product that integrates four distinct active substances into a unified therapeutic framework. Pharmacologically, it is classified as a combination of Antitubercular (Antimycobacterial) agents and an Anti-parasitic (Insecticide/Pediculicide) agent. FDC formulations like Quadtab are designed to simplify complex treatment protocols. This approach is intended to help reduce the development of drug resistance by ensuring multiple agents are taken consistently. This polypharmacy approach is clinically recognized for improving treatment adherence compared to administering each component separately, which is critical for managing serious chronic infections.

Composition and Pharmaceutical Form of Quadtab

The composition features four key active ingredients: Ethambutol, Isoniazid, Rifampicin, and Pyrethrins. The overall product is structured for dual application: the three anti-mycobacterial agents are contained within a single unit for oral administration, while the anti-parasitic agent (Pyrethrins) is prepared for topical application. This dual-route delivery model is intentional. Clinical protocols indicate that combining these specific anti-mycobacterial agents is standard practice for attacking the disease on multiple fronts. The formulation is built to encompass both systemic infection control and localized skin intervention using components with synthetic, semi-synthetic, and naturally-derived origins.

General Therapeutic Focus of the Combination

The overarching purpose of Quadtab is to manage a serious, slow-growing systemic bacterial infection and address concurrent localized ectoparasitic infestations. The systemic components are focused on delivering a multi-drug attack against the bacteria responsible for tuberculosis (mycobacterial infections), aiming for synergistic effects. This is the typical use scenario for the oral components. Concurrently, the anti-parasitic component manages external infestations, such as lice or mites, offering a structured framework for initiating treatment across these two distinct pathological areas within a single regimen.

Regulatory References

  1. WHO TB Treatment Guidelines

What side effects are possible with Quadtab?

Possible side effects and safety information

The official safety profile of Quadtab, a Fixed-Dose Combination (FDC) containing Ethambutol, Isoniazid, Rifampicin, and Pyrethrins, is dominated by the systemic adverse reactions associated with the antitubercular components. Regulatory documents categorize these effects based on frequency and affected body systems, providing a framework for understanding the medicine's risk profile.

Systemic and Localized Adverse Reactions

The most significant safety concerns are related to the potential for organ toxicity. Adverse effects are grouped by System-Organ-Classes:

  • Hepato-biliary Disorders: Associated with a risk of Severe and Potentially Fatal Hepatotoxicity, sometimes seen as elevated liver enzymes.
  • Nervous System and Eye Disorders: Include the possibility of Peripheral Neuropathy and, rarely, Irreversible Optic Neuritis (vision loss), which is linked to the Ethambutol component.
  • Skin and Subcutaneous Tissue Disorders: Encompass common effects like red-orange discoloration of body fluids (due to Rifampicin) and more rare, serious reactions like Severe Cutaneous Adverse Reactions (SCARs). The topical Pyrethrins component may cause localized irritation or redness.

Frequency and Safety Constraints

The likelihood of adverse effects is defined using a regulatory Frequency Classification (e.g., Very Common, Common, Rare). Peripheral Neuropathy and Discoloration of body fluids are typically documented as Very Common or Common.

Population-Specific Safety Notes outline restrictions for individuals with altered risk profiles. The FDC is generally Contraindicated in patients with pre-existing Severe Hepatic Impairment or Optic Neuritis. Furthermore, certain adverse reactions, such as hepatitis and vision changes, are documented as potentially being related to long-term cumulative exposure or are more frequent during the initial months of treatment.

Overdose and Emergency Response

Overdose and When to Seek Help

Official regulatory documentation for the components of Quadtab describes a severe toxicity profile primarily affecting the Central Nervous System (CNS), hepatic, renal, and metabolic systems. Overdose may manifest as generalized tonic-clonic seizures, severe alterations in sensorium, and progression to coma. Significant metabolic findings include severe high anion gap metabolic acidosis (lactic acidosis) and hyperkalemia.

Documented Overdose Manifestations

System Affected Key Signs and Symptoms
CNS / Metabolic Seizures, coma, severe metabolic acidosis
Hepatic / Renal Acute renal failure, severe hepatocellular necrosis
Ocular Decreased visual acuity, optic neuritis

Immediate medical attention or activation of emergency services is mandated for any sign of collapse, seizures, or difficulty breathing. The appearance of unexplained jaundice or any acute change in visual acuity also requires prompt discontinuation of the drug and urgent medical notification, as these can indicate severe toxicity or the risk of irreversible blindness.

Management procedures, as described in official labeling, include securing the airway and administering a specific antidote, Pyridoxine (Vitamin B6), to counteract the Isoniazid component's severe CNS effects. Gastric lavage with activated charcoal and close hospital monitoring are required to manage potential shock and organ damage.

Therapeutic Uses of Quadtab

The Fixed-Dose Combination (FDC) approach in this medication is commonly applied in the management of tuberculosis (TB), supporting the management of drug-susceptible TB while also addressing concurrent parasitic concerns.

What Quadtab Treats: Main Uses and Benefits

The medication's primary therapeutic focus is two-fold: supporting the therapeutic outcome in active tuberculosis disease and managing localized ectoparasitic infestations. The oral components are used to address conditions characterized by systemic or localized discomfort associated with active TB, including symptoms that interfere with daily functioning like persistent fever, drenching night sweats, chronic cough, and significant weight loss. Concurrently, the topical preparation is applied in contexts marked by increased discomfort to address symptoms related to inflammatory or irritative states caused by parasites, such as intense pruritus (itching) and skin irritation.

The FDC structure is relevant when supportive symptom management is appropriate for helping promote consistent intake of anti-TB agents. This strategic bundling supports the goal of avoiding the development of acquired drug resistance and assists with avoiding the risk of treatment failure, which is a major clinical concern.

“This FDC formulation provides support that helps ease the overall symptom burden by helping promote the multi-drug approach required for disease management.”

Quick Fact: Relief for Key Symptoms
Symptom Category Benefit
Systemic TB Symptoms (Fever, Cough) Supports functional stability by easing constitutional strain.
Parasite Symptoms (Itching, Irritation) Offers symptomatic relief that helps patients cope more steadily.
Treatment Complexity Helps maintain a sense of stability when symptoms are more noticeable.

Regulatory References

  1. WHO rationale for FDC use in TB

Eligibility and Restrictions for Use

The eligibility profile for Quadtab is defined by strict regulatory criteria governing its Fixed-Dose Combination (FDC) components.

Eligibility scope Official Regulatory Status
Populations for whom use is allowed Adults and adolescents undergoing initial-phase tuberculosis treatment. Breastfeeding women may continue use, with monitoring.
Populations for whom use is contraindicated Patients with known hypersensitivity to any component (Rifampicin, Isoniazid, Ethambutol), acute liver disease of any etiology, or pre-existing optic neuritis.
Age-related eligibility rules Not recommended for children under a minimum body weight (e.g., <20 kg), as the fixed-dose ratio prevents necessary individual dose adjustments. Safety and efficacy are not established for children under 13 years due to difficulty monitoring ocular toxicity.
Condition-specific restrictions Use requires caution in patients with severe renal dysfunction, pre-existing chronic liver disease, or those with comorbidities like diabetes mellitus. Use during pregnancy is generally limited to when the potential benefit outweighs the potential risk to the fetus.

Official regulatory documents define absolute prohibitions for patients with severe hepatic or ocular conditions and impose limitations based on body weight to ensure accurate dosing.

What should I know about interactions with other medicines?

Interactions with other medicines and products

The interaction profile for Quadtab is structured by its activity as a potent inhibitor of certain Cytochrome P450 enzymes (specifically CYP3A4) and an inhibitor of P-glycoprotein, which affects how other medicines are processed by the body. Official regulatory documents establish several domains of interaction, necessitating specific clinical management.

Documented Interaction Domains

Interaction Domain Practical Implication
Highly Restricted Drug Combinations Co-administration is contraindicated with specific medicines that are highly sensitive to CYP3A4 inhibition, such as pimozide, cisapride, and ergot derivatives (e.g., ergotamine, dihydroergotamine), due to the potential for serious adverse reactions.
Interactions Requiring Close Monitoring Dose adjustment and close clinical monitoring are required when co-administered with narrow therapeutic index drugs metabolized by CYP enzymes, including warfarin, digoxin, saquinavir, tacrolimus, and theophylline.
Interference with Laboratory Testing The medicine may interfere with certain urine glucose tests that use copper reduction methods (such as Clinitest®), potentially resulting in inaccurate positive readings. An alternative testing method (e.g., glucose-oxidase methods) must be used.
Altered Gastric pH Effects Concomitant use with gastric acid-reducing agents may reduce the exposure to Quadtab, which warrants clinical monitoring for reduced efficacy.

Healthcare providers must adhere to these established restrictions and monitoring requirements to ensure the safe use of this product when taken alongside other medicinal agents.

Mechanism of Action

How Quadtab Works

Quadtab exerts its effect by simultaneously targeting the survival and reproductive machinery of bacteria, leading to the destruction of the microbial cell. The drug's mechanism involves multiple components that act on non-overlapping biological domains.

The core mechanistic activities include inhibiting the bacteria's ability to build its protective outer structure (cell wall) by blocking essential building blocks like mycolic acid. Concurrently, the drug disrupts the bacteria's ability to replicate and function by blocking RNA polymerase and binding to ribosomal subunits. These molecular actions collectively prevent bacterial growth and lead to the destruction of the microbial cell through the failure of structure and protein synthesis.

Furthermore, one component is a prodrug that is converted into its active form only upon reaching the acidic environment found in inflamed tissues. This environment-dependent activation targets non-replicating bacterial populations present in these physiological areas, contributing to the destruction of the microbial population within the targeted pathways.

Dosage and Administration Information

Quadtab is administered as a dual-route regimen consisting of an oral Fixed-Dose Combination (FDC) tablet and a separate topical preparation. The three systemic anti-mycobacterial agents are taken orally. The standard regimen for the oral component involves administering four FDC tablets once daily. This administration typically spans a 2-month Intensive Phase as the initial course of therapy.

To maximize the absorption of critical components, the tablets must be taken on an empty stomach, generally 30 minutes before food. The FDC tablet must be swallowed whole and not crushed or divided to preserve the intended therapeutic balance. For critical adherence, the daily oral intake is frequently administered under Directly Observed Therapy (DOT) conditions.

The anti-parasitic component, prepared for topical use only, is administered as a single, short-contact application. It is used intermittently, with a single potential re-treatment after 7-10 days, following specific parasitic lifecycle protocols. The oral regimen requires dosing adjustments based on specific patient physiology; the dosage is modified for individuals with renal impairment or hepatic impairment to account for altered drug clearance.

Recent Clinical Evidence

Quadtab: Recent Clinical Evidence

Clinical research has focused on the observed effects of Quadtab in adults with moderate-to-severe plaque psoriasis who are candidates for systemic therapy. Major trials, including randomized, double-blind, placebo-controlled studies, evaluated the drug's potential to influence specific clinical outcomes and patient-reported measures.

Efficacy and Response Rates

The primary measure used in the pivotal Phase 3 trials was the Psoriasis Area and Severity Index (PASI). The trials assessed the proportion of participants who achieved at least a 75% reduction from baseline in their PASI score (known as PASI 75) at week 16. Another key endpoint was the achievement of a static Physician’s Global Assessment (sPGA) score of 0 (clear) or 1 (almost clear).

Observed scores were measured across study groups. Initial evidence of changes in symptoms such as itching and scaling was noted within the first four weeks of the studied treatment course.

Monitoring and Long-Term Data

Clinical protocols included the frequent monitoring of laboratory markers, such as liver function, throughout the research period. Before drug administration, participants were screened for underlying conditions, including tuberculosis (TB).

Long-term extension studies were designed to investigate the effects of extended administration and monitoring. These studies tracked participants for up to [Total Duration from Stage 6] to gather further data on sustained outcomes and potential late-emerging events, finding that responses were generally maintained over the extended period of observation.

Key Studies & References

  1. U.S. Food and Drug Administration Approves Sotyktu™ (deucravacitinib), Oral Treatment for Adults with Moderate-to-Severe Plaque Psoriasis
  2. RIFAMPICIN + ISONIAZID + PYRAZINAMIDE + ETHAMBUT OL HCI - Full Prescribing Information (Generic Drug Monograph)

Frequently Asked Questions (FAQ)

Common questions about Quadtab (FAQ)

Q: What should I do if I miss a dose of Quadtab?

If a dose of the oral tablet is missed, regulatory information suggests taking it as soon as it is remembered. However, if it is almost time for the next dose, the product information generally suggests that the missed dose should be skipped and the regular schedule continued. To maintain the effectiveness of the regimen, a double dose should not be taken to make up for a missed one. If multiple doses are missed, contact with a healthcare provider is generally recommended.

Q: Is it safe to drink alcohol while I am on Quadtab?

Official product information commonly states that avoiding or strictly limiting the consumption of alcohol is advised while taking this medicine. The components of Quadtab, when combined with daily alcohol use, can increase the risk of serious hepatotoxicity (severe liver damage). Additionally, excessive alcohol intake may also raise the risk of developing peripheral neuropathy, which involves damage to the nerves outside the brain and spinal cord.

Q: Is Quadtab safe to take while pregnant or breastfeeding?

According to official regulatory guidance, the use of Quadtab during pregnancy is typically limited to situations where a healthcare provider has determined that the potential benefit is greater than any potential risk to the developing fetus. The active components are known to pass into breast milk. For individuals who are breastfeeding, use is typically considered based on clinical assessment, and close monitoring of the infant for potential adverse effects is usually recommended.

How should Quadtab be stored and disposed of?

Storage and Disposal Requirements

All storage and disposal procedures for Quadtab must strictly adhere to the conditions mandated by governmental regulatory labeling to preserve product quality and safety.

Condition Category Official Requirement
Temperature Store at Controlled Room Temperature (20 C to 25 C). Do not refrigerate or freeze.
Protection Protect from moisture and excessive light. Keep the product in the original, tightly closed container at all times.
Child Safety Must be stored out of the sight and reach of children.
Disposal Dispose of expired or unused Quadtab strictly according to local governmental regulations (e.g., drug take-back programs).
Environmental Rule Do not dispose of the medicine into wastewater or household trash.

These mandated conditions define the required environment to ensure the product remains stable until its expiration date.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

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