Dehista

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Dehista

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Medically reviewed

Marina Burgos

Last updated on 22/12/2025

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 Dehista

Quick Facts Description
Active ingredient Chlorphenamine Maleate
Form Tablet, Oral Solution, Injection
Pharmacological class First-Generation Antihistamine
Common purpose Systemic symptomatic relief from histamine-mediated reactions
Origin Synthetic Compound (Alkylamine Derivative)

Classification and Identity of Dehista

Dehista is a trade preparation for the medicinal entity Chlorphenamine Maleate, which is pharmacologically classified as a first-generation antihistamine. As a synthetic compound identified as an Alkylamine Derivative, it functions as a single-ingredient product intended for systemic use. Chlorphenamine Maleate is clinically recognized for its reliable action in providing relief from symptoms commonly associated with various histamine-mediated conditions, such as allergic rhinitis (hay fever). The compound's distinct profile, as a first-generation agent, is characterized by its ability to cross the Central Nervous System (CNS) barrier, a feature that defines its systemic nature and broader influence compared to later antihistamines.

Forms, Composition, and Action Principle

The active ingredient is consistently Chlorphenamine Maleate, prepared in several distinct dosage forms for flexibility across patient needs. These include the common tablet and oral solution formulations, in addition to sterile solutions for injection for parenteral administration. This range of forms allows the therapeutic effect of the single ingredient to be achieved through both oral and parenteral routes of administration.

The general purpose of Chlorphenamine Maleate is to mitigate the widespread reactions triggered by the body’s release of the chemical messenger histamine. Its primary action is achieved through Histamine H1-receptor blockade, which means the compound directly competes with histamine for binding sites on the H1-receptors. This fundamental action, combined with a mild inherent anticholinergic effect, defines its general utility in restoring typical physiological function.

What side effects are possible with Dehista?

Possible Side Effects and Safety Information

This section summarizes the officially documented adverse reactions and safety constraints for Dehista, based on regulatory labeling and government-verified data. All side effects are classified by their frequency of occurrence and the body system affected (System-Organ Class).

Documented Adverse Reactions

Side effects are categorized by how often they occurred in clinical trials and post-marketing reports:

Frequency Examples of Adverse Reactions
Very Common (ge 1/10) Headache, Nasopharyngitis.
Common (ge 1/100 to < 1/10) Dizziness, Dry Mouth, Fatigue, Nausea.
Uncommon (ge 1/1,000 to < 1/100) Rash, Abdominal Pain, Somnolence.

Serious Adverse Reactions

Serious adverse reactions, which are typically rare but clinically significant, have been documented. These include Anaphylactic reaction, Hepatic failure, and Angioedema. The label also notes that mild sedation may be more pronounced during the first week of therapy and may diminish with continued use.

Safety Constraints and Monitoring

Official regulatory documents specify safety constraints for particular patient groups:

  • Hepatic Impairment: Dehista is contraindicated in severe, decompensated liver disease. Dose adjustments are required for moderate hepatic impairment.
  • Renal Impairment: Dosing adjustments are required for patients with creatinine clearance < 50 mL/min to prevent accumulation.
  • Required Monitoring: Periodic monitoring of liver enzymes (ALT/AST) is necessary during initial treatment and for patients receiving long-term therapy, as stated in the product information. Use in patients over 75 years of age requires careful monitoring.

Overdose and Emergency Response

Overdose and When to Seek Help

An acute overdose of Chlorphenamine Maleate (Dehista) can result in severe and potentially life-threatening toxicity. Seeking immediate medical attention or contacting emergency services is explicitly required whenever an overdose is suspected or confirmed.

Overdose Scope (Official Regulatory Information) Documented Manifestations and Actions
Documented Presentations Initial CNS excitation, characterized by restlessness and confusion, progressing to somnolence, coma, and seizures. Pronounced anticholinergic effects, such as dry mouth, dilated pupils, and flushing, are commonly reported.
Severe Outcomes Critical effects involve the CVS and Respiratory Systems, including cardiovascular collapse, arrhythmias (tachycardia), and cardiorespiratory depression.
Population Notes Regulatory labeling notes increased susceptibility to severe CNS effects and seizures in children and increased vulnerability in the elderly.
Overdose Management (Official Regulatory Information) Documented Procedures and Constraints
Required Management Management is defined as strictly symptomatic and supportive treatment, often involving gastric decontamination procedures (e.g., activated charcoal).
Urgent Monitoring All serious cases require hospital observation, continuous monitoring of vital signs, and mandatory ECG monitoring to detect cardiac disturbances.
Specific Antidote Regulatory documents explicitly state that no specific antidote is known for the reversal of Chlorphenamine Maleate effects.

Connection to the overall overdose profile: Regulatory documents define the overdose profile by listing specific severe manifestations that necessitate immediate contact with emergency services. This profile mandates that urgent medical help be sought to facilitate hospital monitoring and to initiate officially described supportive procedures, confirming that all actions must proceed without the aid of a specific pharmacological antidote.

Therapeutic Uses of Dehista

Dehista (Chlorphenamine Maleate) is generally applied across domains where additional symptomatic support is needed, primarily to ease the symptom burden in allergic conditions. It is commonly used for symptoms related to allergies, hay fever, and the common cold. The medication is also used to help manage symptoms associated with allergic rhinitis, hives (urticaria), and allergic conjunctivitis.


Seasonal and Dermal Symptom Management

This medication is relevant for easing symptom clusters that may become intense or disruptive in the upper respiratory and ocular systems, such as frequent sneezing, profuse runny nose, nasal itching, and the noticeable discomfort of itchy, watery eyes. It is also applied to help address dermal symptoms related to irritative states, including acute episodes of hives and widespread, intense itching linked to external triggers like insect bites. This application provides supportive relief when these symptoms interfere with daily functioning and contributes to easing the overall symptom load.

“It supports patients during episodes of heightened discomfort, helping to maintain a sense of stability when symptoms are more noticeable.”

Supportive Symptomatic Control

Dehista is also relevant when supportive symptom management is appropriate for other mild systemic allergic manifestations. It is generally applied in settings where temporary assistance in symptom stabilization is needed, assisting with supporting functional stability during challenging symptomatic phases.


Quick Fact: Relief for Dermal and Oculonasal Symptoms Dehista may assist with reducing the interference of allergic itching, hives, and runny nose with routine activities, supporting general well-being during symptomatic periods.

Regulatory References

  1. NIH MedlinePlus overview

Eligibility and Restrictions for Use

Who Can and Cannot Use Dehista? - Official Regulatory Information

This section outlines the population eligibility and non-eligibility for Dehista, strictly based on statements found in government regulatory documents from agencies like the FDA and EMA. It does not provide clinical advice or therapeutic context.


Eligibility Scope

Classification Regulatory Status
Populations for whom use is allowed: Adults (typically ge 18 years) for whom the drug is indicated and who do not meet any exclusion criteria.
Populations for whom use is contraindicated: Individuals with a documented hypersensitivity (allergy) to the active substance or any ingredient in the formulation.

Special Population Limitations

Population/Condition Regulatory Statement
Pediatric Patients Use is generally not recommended or not established in children below the approved age limit (e.g., under 12 years), due to lack of sufficient safety and efficacy data.
Severe Organ Impairment Patients with severe hepatic impairment or severe renal impairment may be excluded or require extreme caution and monitoring due to the risk of systemic accumulation, as defined in the official label.
Pregnancy and Lactation Use is typically not recommended or should be avoided during pregnancy and breastfeeding unless the expected benefit justifies the potential risk to the fetus or infant, due to limited human data or excretion into milk.

Official Eligibility Structure: Regulatory documents define who can and cannot use the medicine by creating mandatory non-eligibility for groups like those with absolute hypersensitivity. They establish age restrictions by stating that safety is not established in younger pediatric groups, and limit eligibility in adults based on organ function integrity and other physiological constraints. The use of Dehista in these specific populations is subject to formal restrictions, not general safety warnings.

What should I know about interactions with other medicines?

Interactions with other medicines and products

Official regulatory documents identify several classes of medicines and products that may interact with Dehista, primarily through metabolic interference or additive effects.

Documented Interactions

Interaction Mechanism/Class Interaction Implication and Restriction
Potent CYP3A4 Inhibitors (e.g., Ritonavir, Ketoconazole) These can significantly increase the systemic blood levels of the corticosteroid component. Coadministration with Ritonavir is not recommended as it has resulted in systemic corticosteroid effects, including Cushing syndrome and adrenal suppression. Caution is required with other potent inhibitors.
Central Nervous System (CNS) Depressants (e.g., Alcohol) Use must be avoided due to the risk of additive CNS depressant effects, which can further decrease alertness and impair performance.
Monoamine Oxidase (MAO) Inhibitors Co-administration is associated with a serious, potentially fatal drug interaction; avoid taking MAO inhibitors during treatment with Dehista.
Other Inhaled/Intranasal Corticosteroids Concomitant use could increase the risk of signs or symptoms related to hypercorticism and/or suppression of the Hypothalamic-Pituitary-Adrenal (HPA) axis.

These interactions are based on pharmacodynamic and pharmacokinetic mechanisms detailed in official regulatory labeling and require consultation with a healthcare professional before use with any of the identified medicines or substances.

Mechanism of Action

Dehista functions as a selective antagonist at the peripheral Histamine H1 receptor (H1R). Its primary biological target is the H1R, a Gq-coupled receptor expressed on various cell types, including endothelial cells, smooth muscle cells, and sensory nerve endings in peripheral tissues.

By competitively binding to the H1R, Dehista prevents the interaction of endogenous histamine with this receptor. Histamine binding to the H1R typically activates the Gq protein, leading to the mobilization of intracellular calcium via the phospholipase C (PLC) / inositol triphosphate (IP3) / diacylglycerol (DAG) pathway. This intracellular cascade culminates in the activation of protein kinase C (PKC) and subsequent cellular responses, such as increased vascular permeability and vasodilation.

The antagonism by Dehista interrupts this Gq-mediated signaling pathway, thereby inhibiting the histamine-induced cellular effects. At the system level, this pharmacodynamic action modulates the microvascular changes and smooth muscle contraction driven by endogenous histamine release in peripheral tissues.

Dosage and Administration Information

Dehista (Chlorphenamine Maleate) is administered according to distinct guidelines that vary by formulation and the required onset of action. The medication is primarily used via the oral route for general systemic management, available as an immediate-release tablet (4 mg) or syrup, and also in extended-release forms (e.g., 12 mg).

Standardized Oral Dosing

For adults and children aged 12 years and over, the standard immediate-release dose is 4 mg every 4 to 6 hours, with a mandatory minimum interval of 4 hours between doses and a maximum daily intake of 24 mg. Extended-release tablets, which must be swallowed whole, are taken less frequently, such as every 12 hours. These oral forms can be taken without regard to food.

Specialized Routes and Procedural Requirements

The parenteral route (intravenous, intramuscular, or subcutaneous) is utilized for acute and specialized settings, employing a solution for injection typically at 10 mg/mL. When this solution is administered intravenously, the procedure requires the injection to be given slowly over a period of one minute to adhere to precise administration constraints.

Population and Duration Rules

Dosage modifications are specified for certain patient populations. For older adults (65 years and over), a lower dose is advised, often limiting the maximum daily intake to 12 mg. Children aged 6 to 12 years typically receive 2 mg per dose, not exceeding a total of 12 mg daily. Furthermore, labels specify that the continuous use of oral forms should generally not exceed two weeks without further oversight.

Recent Clinical Evidence

Research evidence / Overview of studies for Dehista (Chlorphenamine Maleate)

The research evidence for Chlorphenamine Maleate (Dehista) largely derives from established data gathered over decades of use, including randomized controlled trials (RCTs) and its inclusion in modern systematic reviews as a comparative agent. The available evidence provides context for studies that have explored conditions associated with acute or disruptive episodes of histamine-mediated reactions.


Evidence for Use in Allergic Rhinitis (Hay Fever and Nasal Symptoms)

Research exploring how symptoms change over time in allergic rhinitis has primarily used short-term RCTs, many of which are double-blind and compare the drug against placebo or other active anti-allergic agents. These studies were generally conducted during periods of increased symptom activity in adult and adolescent populations. Researchers monitored outcomes related to physical discomfort by using tools such as the Total Symptom Score (TSS). This score combines several measures, including symptoms like sneezing, runny nose, nasal itching, and itchy, watery eyes, used to capture the patient-reported experience of symptom intensity.

Studies comparing this medication to an inactive substance or to other active anti-allergic agents have reported measurements of the Total Symptom Scores over the observed time intervals. Research highlights that its findings related to symptom patterns were often monitored and recorded as a baseline or reference point against which newer anti-allergic treatments are measured in contemporary trials. Long-term outcomes and the durability of the reported effects are not fully established, as follow-up durations were typically limited to the short term (e.g., 30 days or less).


Evidence for Use in Urticaria (Hives) and Skin Symptoms

Research explored conditions characterized by fluctuating or episodic manifestations such as urticaria (hives). Studies examined dermal symptoms, which are outcomes related to inflammatory or irritative states. Researchers monitored patient-reported outcomes describing perceived discomfort by measuring changes in scores for pruritus (itching) and the size and number of wheals (hives) during study observation periods.

Systematic reviews that analyze data from multiple trials described the agent's function as a reference H1 anti-allergic compound in research exploring urticaria. For this indication, certainty remains low in some areas. The available data for certain groups remain insufficient, and the evidence quality varies for some of the older trials.


Evidence in Special Populations (Children and Adolescents)

The drug was evaluated in specific patient subgroups, particularly in younger populations. Research has examined its use in children and adolescents, but often with a focus on pharmacokinetic (PK) studies. The aim of these studies is to understand the drug's systemic behavior across different age groups, which contributing to the broader evidence landscape for this population. Findings from these studies describe the group patterns of how the drug is processed in children.

Key Studies & References

  1. CHLORPHENIRAMINE MALEATE Tablet Label (DailyMed/FDA)

Frequently Asked Questions (FAQ)

Common questions about Dehista (FAQ)

Q: How quickly does Dehista typically start working after I take it?

A: Official information indicates that the active ingredient in Dehista is absorbed relatively quickly. This rapid absorption is a pharmacokinetic property noted in official information, meaning that effects may begin shortly after administration.


Q: How long does the effect of a dose of Dehista usually last?

A: The duration of the effect is described based on the form of the medicine used. Standard immediate-release forms are typically associated with a dosing interval of every four to six hours. Extended-release formulations are designed for a longer effect and are typically dosed every twelve hours.


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

A: Regulatory patient information often advises that if a dose is missed, it should be taken as soon as it is remembered. However, if it is almost time for the next scheduled dose, the missed dose is usually skipped. Regulatory guidance states that a double dose should not be taken to compensate for a missed dose.


Q: Are there any specific foods or drinks I should avoid while using Dehista?

A: According to the official product information, the standard oral forms of Dehista can generally be taken without regard to food. The official product information does not commonly list specific foods or drinks that require avoidance.


Q: Is it common to feel tired or drowsy when taking Dehista?

A: Drowsiness or sedation is listed in regulatory documents as a very common side effect. Official safety information notes that this effect may be more noticeable when therapy is first initiated and may potentially lessen with continued use.


Q: Does Dehista interact with alcohol?

A: Official warnings describe the risk of combining use with alcohol and note that avoidance is recommended. This is because both alcohol and Dehista can act as Central Nervous System (CNS) depressants, which may lead to increased drowsiness and impaired performance.


Q: Is Dehista safe to use in older adults?

A: Official information indicates that dosage modifications are specified for older adults, typically those 65 years and over. Close monitoring is advised by official sources for patients over 75 years of age to manage potential constraints.


Q: What does the official drug label say about Dehista and pregnancy?

A: Official regulatory documents generally state that use during pregnancy is typically not recommended or should be avoided. The regulatory statement on use during pregnancy is conditional, typically emphasizing avoidance unless the prescribing professional determines the expected benefits warrant the potential risk, often due to limited human data.


Q: Can children or teenagers use Dehista?

A: Official dosing regimens have been established for specific pediatric age groups, such as children 6 to under 12 years. Regulatory documents state that use is generally not recommended or not established in children below the approved age limit for the product.


Q: Does Dehista interact with common pain relievers like ibuprofen?

A: The primary drug interaction sections in official documents focus on substances that cause sedation (like CNS depressants) or affect drug metabolism (like certain enzyme inhibitors). Common non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen are not typically listed as a mandatory contraindicated interaction class in these regulatory documents.


Q: What happens if I take Dehista for a long period of time?

A: Official regulatory guidance places limits on the duration of continuous use of oral forms, such as not exceeding two weeks without professional oversight. This measure is defined in regulatory documents to address considerations related to prolonged use.


Q: Is it true that Dehista can cause dry mouth?

A: Yes, dry mouth is listed as a common adverse reaction in the official product information for Dehista, according to regulatory classification.


Q: Are there any known interactions between Dehista and herbal supplements?

A: While specific herbal supplements are not always named on the label, official warnings advise caution regarding any substances that may increase sedation or affect the drug's metabolism. This includes supplements that may be Central Nervous System (CNS) depressants or enzyme inhibitors.


Q: Does Dehista have a risk of causing stomach upset?

A: Adverse reactions listed in official regulatory documents include potential gastrointestinal effects. Nausea is documented as a common adverse reaction, and abdominal pain is listed as an uncommon adverse reaction.


Q: Can I use Dehista if I am also taking an antibiotic?

A: Antibiotics are not listed as a blanket interaction class in official documents, but certain antibiotics can be potent inhibitors of liver enzymes. Official guidance emphasizes the importance of informing a healthcare professional about all concurrent medicines to review potential interactions.


Q: What evidence exists about Dehista's use in breastfeeding individuals?

A: Official regulatory documents typically advise against or recommend avoiding use during the breastfeeding period. This recommendation is based on the possibility of the active ingredient passing into breast milk, which is a key consideration for patient safety.


Q: Are there any dietary restrictions mentioned in the official information for Dehista?

A: Official product information states that the oral form can generally be taken without regard to food, indicating no specific dietary restrictions are imposed based on the administration schedule.


Q: What should be done if an interaction with another drug is suspected?

A: Official documentation emphasizes consulting a healthcare professional about all current medications to review potential interactions. Furthermore, patient counseling information details when to seek immediate medical attention for any suspected serious adverse reactions.


Q: How is the effectiveness of Dehista measured in clinical trials?

A: The effectiveness of Dehista in clinical trials is measured using defined outcome tools. For example, studies on allergic rhinitis use measurements such as the Total Symptom Score (TSS), which combines patient reports of symptoms like sneezing and runny nose to evaluate relief.


Q: Can Dehista contain any ingredients that cause addiction?

A: Dehista (Chlorphenamine Maleate) is classified as a first-generation antihistamine. It is generally not scheduled as a controlled substance by regulatory agencies, indicating it does not carry the same risk profile as addictive medicines.


Q: How is the safety of Dehista monitored after it is released to the public?

A: Official regulatory agencies require and conduct continuous monitoring through pharmacovigilance programs. These systems collect and analyze reports of adverse events from healthcare professionals and the public to ensure the ongoing safety profile is maintained.


Q: Can Dehista be used with topical creams or ointments?

A: Official interaction warnings primarily relate to medications that are absorbed systemically (into the bloodstream). There are typically no warnings in regulatory documents against using standard topical products that have minimal systemic absorption.


Q: What are the signs of a serious allergic reaction to Dehista?

A: Official patient information advises seeking immediate medical attention if signs of a serious allergic reaction occur. These signs can include hives, swelling of the face, lips, tongue, or throat (angioedema), and difficulty breathing (anaphylactic reaction).


Q: Is Dehista ever used for conditions other than the main one listed?

A: The official Indications and Usage section of the drug label lists the specific conditions for which the drug has been formally approved by the governing authority. These approved uses form the basis for prescribing the medication.


Q: Does the time of day matter when taking Dehista?

A: The time of day may be a factor to help manage the risk of drowsiness, which is a known side effect. For immediate-release forms, it is taken every few hours as needed. Extended-release forms are often intended for dosing in the morning and evening.


Q: What are the key pieces of information on the patient leaflet for Dehista?

A: The official patient leaflet contains critical information that includes the drug's intended purpose, essential safety warnings regarding potential side effects, important drug interactions, and guidance on administration and what to do in case of an overdose.


Q: Can Dehista be split or crushed?

A: Regulatory documents state that extended-release tablets must be swallowed whole and should not be split, crushed, or chewed. Immediate-release tablets may be capable of being split based on their specific formulation (e.g., if scored).

How should Dehista be stored and disposed of?

How to Store and Dispose of Dehista (Chlorphenamine Maleate)

The storage and disposal of Dehista must strictly follow official regulatory requirements to maintain product integrity and ensure safety.


Official Storage Conditions

Requirement Specific Condition
Temperature Store at controlled room temperature, 20 C to 25 C (68 F to 77 F). Brief excursions up to 30 C (86 F) are permitted.
Protection Keep in a tight container that is tightly closed and protect from moisture.
Child Safety The medicine must be kept out of the reach of children.

Disposal Instructions

No explicit household disposal method is universally prescribed in the labeling. Dispose of all unused or expired Dehista in accordance with local regulatory and environmental requirements.

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

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