What Contac 400 Treats: Main Uses and Benefits

The medication is commonly used across conditions presenting with acute episodes of the common cold and allergic rhinitis, including hay fever. The utility of this combination is relevant for managing symptom clusters that interfere with daily comfort and often appear simultaneously: excessive secretion and airway obstruction.

Managing Acute Symptoms of the Common Cold

It is applied in clinical settings that involve acute or disruptive symptom patterns, and often used when symptoms intensify and supportive relief is needed. The medication helps address manifestations such as a runny nose, frequent sneezing, and the physical discomfort of nasal congestion.

Addressing the Dual Burden of Congestion and Secretion

The combination contributes to easing the overall symptom load by supporting the reduction of flow symptoms while also diminishing the swelling responsible for a stuffy nose and sinus pressure. It is relevant for easing symptoms related to inflammatory or irritative states, such as the intense itchy nose and watery eyes.

Quick Fact: Relief for Dual Symptoms The formula is primarily applied in scenarios where additional symptomatic support is needed for both allergic irritation and nasal blockage, and may assist with maintaining functional stability and contributing to improved comfort.

Regulatory References

1. Philippine FDA Verification Portal

The eligibility profile for Contac 400 is strictly defined by regulatory warnings associated with its active components. Use is not recommended in several major global markets, including the United States, Canada, and Australia, where regulatory agencies have advised against products containing Phenylpropanolamine (PPA).

Absolute Contraindications

The medicine is strictly contraindicated and must not be used by individuals with certain health conditions, including:

• Patients currently taking or who have taken a Monoamine Oxidase Inhibitor (MAOI) within the last 14 days.
• Individuals with severe, uncontrolled high blood pressure, coronary artery disease, or hyperthyroidism.
• Patients diagnosed with glaucoma or those experiencing difficulty in urination due to an enlarged prostate.

Age and Life-Stage Restrictions

• Age: The medicine is not recommended for use in children under 12 years of age. Older adults (over 60) should use it with caution, as they may be more susceptible to adverse effects.
• Pregnancy/Lactation: The medicine is not recommended for women who are breastfeeding. Pregnant women must consult a health professional prior to use.

Conditional Eligibility

Use requires professional consultation for individuals with pre-existing conditions like diabetes, kidney or liver disease, emphysema, or chronic bronchitis.

Interactions with other medicines and products

The following section summarizes officially documented drug and substance interactions for Contac 400, a combination product typically containing acetaminophen, a decongestant, and an antihistamine/antitussive, based on authoritative regulatory information.

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Contraindicated Combinations and Timing Restrictions

Classification	Interacting Substance/Class	Official Constraint
Forbidden	Monoamine Oxidase Inhibitors (MAOIs)	Must not be used concurrently or within two weeks of stopping an MAOI.
Forbidden	Other Acetaminophen Products	Avoid co-administration to prevent exceeding maximum daily dose and limit hepatotoxicity risk.

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Clinically Significant Pharmacodynamic Interactions

Co-administration with other Central Nervous System (CNS) depressants, including sedatives, tranquilizers, and other antihistamines, may result in additive effects, increasing drowsiness and sedation. Similarly, combining with other sympathomimetics or stimulants can potentiate effects such as increased heart rate and blood pressure.

Interactions with Food, Alcohol, and Specific Medications

• Alcohol: Consumption of alcohol is restricted due to a documented increase in the risk of severe liver damage associated with the acetaminophen component, in addition to enhanced CNS depression.
• Oral Anticoagulants (e.g., Warfarin): Chronic or high-dose use of the acetaminophen component requires monitoring, as it may increase the anticoagulant effect.
• Caffeine: Limiting excessive caffeine intake is advised due to the potential for additive stimulant effects from the decongestant component.

Regulatory documents emphasize that patients with a history of regular alcohol use are at increased risk of acetaminophen-related hepatotoxicity.

The physiological effects of Contac 400 are produced through the integrated action of its two components, engaging and modulating key biological systems responsible for inflammatory signaling and vascular tone.

Molecular Blockade of the Histamine H1 Receptor

The mechanism for Chlorpheniramine involves inverse agonism at the Histamine H1 Receptors ( H1R). By stabilizing the H1R in an inactive state, the drug functionally inhibits the signaling cascade triggered by histamine, a specific signaling molecule. This action inhibits the H1-mediated increase in capillary permeability and glandular hypersecretion, resulting in a reduction in fluid extravasation and secretion within the respiratory tract.

Indirect Activation of Alpha Adrenergic Receptors

Phenylpropanolamine acts via an indirect sympathomimetic mechanism, displacing Norepinephrine (NE) from presynaptic terminals. The released NE then activates Alpha-1 (alpha1) Adrenergic Receptors on the vascular smooth muscle of nasal blood vessels. This receptor activation causes immediate local vasoconstriction which reduces the local blood volume associated with vascular engorgement, resulting in a change in mucosal tissue volume.

Central Spillover and Anticholinergic Modulation

Chlorpheniramine’s lipophilicity allows it to cross the blood-brain barrier, resulting in off-target antagonism at central H1 and Muscarinic Acetylcholine Receptors. This central spillover mechanism results in H1 and muscarinic receptor activity in the CNS. Peripherally, the anticholinergic component further suppresses the parasympathetically driven mechanism of glandular secretion.

The administration of upper respiratory combination products under the Contac brand, such as formulations containing Chlorpheniramine and a decongestant, is characterized by a standardized oral regimen. The single method of administration is the oral route.

Official Usage Patterns

Dosing and Frequency:

For adults and pediatric patients 12 years of age and over, the standardized unit dose is two caplets or tablets per single administration. This fixed dose is intended for intermittent use (as needed) and must be separated by a mandatory minimum interval of six hours. There is a maximum total intake requirement that individuals do not exceed eight units within any 24-hour period.

Duration and Age Rules:

The medicine is used for short-term management and is not intended for use exceeding seven consecutive days without medical oversight. The medication is indicated for individuals 12 years of age and older. Administration to children under this age is performed only following consultation with a health professional. No specific instructions are detailed regarding timing in relation to meals or preparation requirements prior to ingestion. The core procedural constraint is the imperative to adhere strictly to the maximum recommended daily dose.

Recent Clinical Evidence Overview

Efficacy Studies

Clinical research on combination cold and flu preparations, such as those containing acetaminophen, chlorpheniramine, and the decongestant phenylephrine (one component of Contac 400), focuses on the relief of common symptoms like headache, runny nose, and nasal congestion.

Randomized, controlled trials have evaluated the effects of these combinations in adults with cold and flu-like syndromes. Studies utilize symptom scoring scales, overall duration of symptoms, and return to usual activities as key measurements of potential benefit.

Note on Decongestants: Recent scientific reviews and regulatory advisory committees in certain jurisdictions have re-evaluated the effectiveness of oral phenylephrine as a nasal decongestant. Current data suggests that at the dosage levels commonly sold over-the-counter, oral phenylephrine is not superior to placebo in relieving nasal congestion in adults.

Safety and Tolerability

Clinical data indicates that cold and flu combination drugs are generally associated with a range of reported adverse effects, often mild to moderate. The most frequently observed effects in trials of similar formulations include:

• Drowsiness/Sedation (due to the antihistamine component)
• Dry mouth
• Dizziness and Headache
• Gastrointestinal symptoms (e.g., nausea)

Individuals with pre-existing conditions, particularly cardiovascular issues, may be excluded from trials, as decongestant components (e.g., phenylephrine or pseudoephedrine, depending on the specific product formulation) can cause changes in blood pressure or heart rate. All components are associated with potential drug-drug and drug-disease interactions, requiring careful assessment by a healthcare provider.

Common questions about Contac 400 (FAQ)

Q: What is the difference between Contac 400 Day and Contac 400 Night formulas?

Official labeling shows a difference in the active ingredients between the Day and Night versions. The Day formula typically contains a pain reliever and a decongestant. The Night formula includes an additional antihistamine component, which is associated with temporary relief of symptoms such as sneezing and runny nose. This component is also documented as potentially causing drowsiness.

Q: Can Contac 400 be used by elderly individuals (65 years and older)?

Official warnings indicate that caution is necessary when the medicine is used by older adults (aged 65 years and older). Regulatory documents note that older adults may be more susceptible to certain effects, such as dizziness, drowsiness, confusion, and difficulty with urination, when compared to younger adults.

Q: What is the risk associated with taking too much acetaminophen, an ingredient in Contac 400?

Regulatory documents include a critical warning about the acetaminophen component. Exceeding the maximum recommended daily amount of acetaminophen, from this product or others, can lead to the risk of severe liver damage. The potential for severe liver injury, which can be life-threatening, is a critical warning associated with exceeding the maximum dose.

Q: Why do certain retailers keep some Contac 400 products behind the pharmacy counter?

In certain countries, regulatory laws require that products containing specific decongestant ingredients, such as pseudoephedrine or phenylpropanolamine, be kept behind the pharmacy counter. These measures are regulatory requirements put in place to control the sale quantities of these ingredients, which have been identified as precursor chemicals for illicit manufacturing.

Q: What kind of research evidence supports the combination of ingredients in Contac 400?

Evidence from clinical research has focused on the temporary relief of common cold and flu symptoms associated with the use of combination products. However, official information also notes that regulatory advisory committees in some jurisdictions have re-evaluated the effectiveness of certain decongestant components at the commonly sold dosage levels.

Q: Can Contac 400 be used by patients with heart problems?

Official precautions advise that individuals with pre-existing heart problems, high blood pressure, or a history of coronary artery disease must consult a health professional prior to using this product. Regulatory precautions specify that consultation with a health professional is required prior to using this product because of the decongestant component’s potential to affect the cardiovascular system.

Q: Is Contac 400 safe for individuals who have liver disease?

Official labeling advises that individuals with liver disease must consult a health professional prior to use. This is due to the documented risk of severe liver damage associated with the acetaminophen component. Professional consultation is required to assess individual eligibility.

Q: Does Contac 400 have any effect on asthma or other breathing problems?

Official documents specify that conditions such as asthma, emphysema, and chronic bronchitis are listed as health problems for which professional consultation is required before the medicine is used. This is a common precaution for products containing decongestants or antihistamines.

Q: What is meant by the 'multi-symptom relief' feature of Contac 400?

The term refers to the product's ability to temporarily relieve several cold and flu symptoms simultaneously. Official information indicates these symptoms typically include nasal congestion, minor aches, fever, and symptoms like sneezing and runny nose, based on the approved uses of its active ingredients.

Q: Is it possible for Contac 400 to interact with blood-thinning medications?

Official interactions list states that chronic or high-dose use of the acetaminophen component with oral anticoagulants, such as Warfarin, may require monitoring. This interaction may increase the anticoagulant effect, and official information states that monitoring is required.

Q: Does Contac 400 have an effect on stomach upset or nausea?

Official safety information includes stomach upset and nausea among the range of possible effects that may occur. These are typically listed among the mild to moderate gastrointestinal symptoms reported with the use of the medicine.

How to Store and Dispose of Contac 400

The storage and disposal of this medication must align strictly with official regulatory labeling to ensure product stability and safety.

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Storage Conditions

Contac 400 must be stored at controlled room temperature, specifically between 20 C to 25 C (68 F to 77 F). The product should be protected from excessive heat and moisture and must remain in its tightly closed original container. It is a mandatory requirement to keep Contac 400 out of the sight and reach of children.

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Disposal Instructions

Unused or expired medication must be properly discarded and should not be flushed down the toilet or poured into a drain. Disposal should utilize drug take-back programs when available. If take-back is not an option, the medication should be mixed with an unappealing substance, sealed in a bag, and placed in the trash.