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Quitazine

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Quitazine

Quitazine_EN

Method of action: Antiallergic, Antiemetic, Antipruritics, Incl. Antihistamines, Anesthetics, Etc, Hypnotic, Sedative

Treatment option: Anaphylaxis, Insomnia, Hives, Rhinitis, Hay Fever

Medically reviewed

Rosario Oropesa

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 Quitazine

Quick Facts

Property Description
Active ingredient Promethazine hydrochloride
Form Tablet, Syrup, Suppository, Injection
Pharmacological class First-generation Antihistamine, Antiemetic
General purpose Relief of allergic symptoms, nausea, and to provide sedation
Origin Synthetic, Phenothiazine derivative

What Type of Medicine is Quitazine, and What is its Active Ingredient?

Quitazine is a synthetic, single-ingredient pharmaceutical preparation whose sole active component is Promethazine, typically formulated as the hydrochloride salt. Promethazine is structurally identified as a phenothiazine derivative, which places Quitazine within the broader phenothiazine family of compounds. Pharmacologically, it is classified as a first-generation antihistamine and a potent antiemetic. The classification as a first-generation antihistamine is significant because it indicates the drug readily affects the central nervous system, leading to its characteristic pronounced sedative effect.

Forms and Composition: How is Quitazine Supplied?

Quitazine is supplied in several distinct dosage forms to accommodate various patient needs and routes of delivery. These preparations include film-coated tablets and oral syrup/solution for consumption by mouth, as well as rectal suppositories, and specialized parenteral injection solution. The composition consists of the active Promethazine ingredient combined with the necessary pharmaceutical excipients. The wide array of forms, particularly the injection solution, highlights its established role in environments where rapid, reliable symptom control, such as managing severe post-operative nausea, is necessary.

What is the General Purpose of Taking Quitazine?

The general purpose of taking Quitazine is to manage symptoms broadly associated with allergic conditions, to control feelings of nausea and vomiting, and to induce sedation. Its chemical structure allows it to powerfully block histamine, which helps mitigate symptoms like itching and swelling, while its influence on brain centers helps to calm signals related to motion and the urge to vomit. This combined action profile means the medicine is utilized for its capacity to address symptoms arising from overactive bodily responses and to provide general symptomatic relief, particularly when pronounced drowsiness is either desired or therapeutically acceptable.

Regulatory References

  1. Promethazine: MedlinePlus Drug Information
  2. Promethazine - StatPearls - NCBI Bookshelf

What side effects are possible with Quitazine?

Possible Side Effects and Safety Information

The official safety profile for Quitazine (Promethazine hydrochloride) is structured around categories of adverse reactions as documented in government regulatory labeling.

Adverse effects are primarily related to the drug's effects on the Central Nervous System (CNS) and its anticholinergic properties.

Adverse Reaction Classification

Classification Examples of Officially Listed Effects
Common Drowsiness, sedation, blurred vision, dry mouth, dizziness, fatigue, disturbed coordination.
Rare Hypotension, leukopenia, agranulocytosis.
Frequency Not Known Neuroleptic Malignant Syndrome (NMS), convulsions/seizures, severe respiratory depression.

Common effects, such as somnolence, are typically most pronounced during the initial phase of treatment or following a dosage adjustment, as specified in regulatory documents. Adverse reactions are grouped by System-Organ Class, affecting the Nervous System, Blood and Lymphatic System, Gastrointestinal System, and Skin.

Serious Adverse Reactions and Safety Constraints

Regulatory documents list Severe Respiratory Depression as a serious adverse reaction, particularly noting risk in vulnerable groups. Neuroleptic Malignant Syndrome (NMS) and rare hematologic events like Agranulocytosis are also officially documented.

Population-specific safety considerations include a strict contraindication for pediatric patients under two years old due to the officially recognized risk of potentially fatal respiratory depression. The medicine is also contraindicated in patients in a comatose state or those presenting with lower respiratory tract symptoms, consistent with regulatory safety restrictions. The official information underscores the spectrum of risks, from common CNS effects to rare, serious systemic events.

Overdose and Emergency Response

Overdose: When to Seek Help

Official government regulatory information defines the overdose profile of Quitazine (Quetiapine) based on documented clinical experience. Overdose is characterized by symptoms primarily affecting the Central Nervous System (CNS) and the Cardiovascular System.

Documented Overdose Manifestations

System Affected Common Signs and Symptoms
CNS Drowsiness, profound sedation, delirium, confusion, and potential progression to coma and seizures (convulsions).
Cardiovascular Sinus tachycardia (fast heart rate), hypotension (low blood pressure), and QT interval prolongation (an electrical change in the heart).

Serious Outcomes and Immediate Action

Life-threatening consequences include respiratory depression (slowed or shallow breathing), circulatory collapse (severe shock), and cardiac arrest. Immediate medical attention is required for any suspected overdose or if the patient exhibits severe drowsiness, confusion, loss of consciousness, or difficulty breathing.

Management is supportive and symptomatic, focusing on maintaining a patent airway and ensuring adequate oxygenation and ventilation. Continuous monitoring of cardiac function (ECG) and blood pressure is critical. While there is no specific antidote, measures like administering activated charcoal may be considered in early stages to reduce absorption. Due to the potential for delayed or prolonged effects, particularly with extended-release formulations, extended observation in a medical facility is often required.

Therapeutic Uses of Quitazine

What Quitazine Treats: Main Uses and Benefits

Quitazine is commonly used to help manage symptoms across multiple domains where short-term symptomatic assistance is needed. The medication is applied across therapeutic areas including the management of allergic symptoms, the control and prevention of nausea and vomiting, and is relevant for situational sedation and relief of apprehension.

It is relevant for managing conditions characterized by episodic or fluctuating manifestations, such as seasonal allergic rhinitis, uncomplicated urticaria (hives), motion sickness, and postoperative emesis (vomiting). The supportive relief it provides contributes to easing the overall symptom load, helping the patient cope more steadily during difficult episodes.

“This medication is considered relevant in contexts marked by increased discomfort or tension, offering supportive relief when symptoms become temporarily overwhelming.”

This makes Quitazine useful in clinical settings that involve acute or unstable symptom patterns, and is commonly used to help with support during phases of increased distress or discomfort.

Quick Fact: Relief for Key Symptom Clusters : Quitazine is commonly used to address itching (pruritus) and allergic irritation, to help manage nausea and vomiting episodes, and is relevant for easing restlessness and situational anxiety.

Eligibility and Restrictions for Use

Quitazine (Promethazine) eligibility is determined by strict regulatory rules regarding age, central nervous system (CNS) status, and pre-existing medical conditions.

Contraindications and Prohibited Use

Quitazine is contraindicated (must not be used) in the following populations, according to official regulatory labeling:

  • Children less than 2 years of age, due to the potential for fatal respiratory depression (FDA Boxed Warning).
  • Comatose patients or those with a state of severe CNS depression.
  • Individuals with a known hypersensitivity to promethazine or any other phenothiazine derivative.
  • Patients with lower respiratory tract symptoms, including acute asthma.

Age-Specific Eligibility and Restrictions

Age Group Eligibility Status (Regulatory) Restriction Rationale
Infants (<2 years) Contraindicated Fatal respiratory depression risk.
Children (2–5 years) Conditional/Restricted Use with caution at the lowest effective dose; some regions restrict oral use under 6 years.
Older Adults (65+ years) Conditional/Restricted Use with caution due to increased susceptibility to anticholinergic effects (Beers Criteria).

Conditional Use and Comorbidity Restrictions

Use of Quitazine requires caution in patients with specific pre-existing conditions, including narrow-angle glaucoma, prostatic hypertrophy, seizure disorders (may lower seizure threshold), severe renal impairment, impaired liver function, and pyloroduodenal or bladder-neck obstruction.

Pregnancy and Lactation

Use during pregnancy is conditional; it is only permitted if the potential benefit justifies the potential risk to the fetus, and use is generally avoided late in the third trimester. For lactation, use is not generally recommended, and a decision must be made to discontinue nursing or discontinue the drug.

What should I know about interactions with other medicines?

Quitazine Interactions with other medicines and products

Quitazine's interaction profile is documented in regulatory sources and primarily involves additive effects with agents affecting the central nervous system (CNS).

Classification Interacting Substances/Context
Contraindicated Combinations Co-administration is prohibited in comatose states and following large doses of other CNS depressants. Epinephrine must not be used to treat hypotension during a Quitazine overdose, as it may reverse the vasopressor effect.
Pharmacodynamic Reinforcement The sedative action of CNS depressants (including alcohol, narcotics, barbiturates, general anesthetics, and tranquilizers) may be increased, prolonged, or intensified. Additive effects also occur with Anticholinergics and MAOIs, potentially intensifying CNS depression.
Metabolic Involvement Quitazine is documented as being metabolized by the hepatic enzyme CYP2D6 (substrate status).

Regulatory documents stipulate specific restrictions for co-use. For example, when Quitazine is given with Narcotics or Barbiturates, the dose of the narcotic or barbiturate should be reduced by one-quarter to one-half or at least one-half, respectively. In pediatric patients 2 years of age and older, co-administration with other respiratory depressant effects must be avoided. Additionally, Quitazine may cause interference with certain diagnostic products, leading to false-positive or false-negative results in immunological pregnancy tests and allergen skin tests.

Mechanism of Action

Quitazine's mechanism of action is defined by its non-selective neurotransmitter receptor antagonism. Its effects are initiated by rapid passage across the blood-brain barrier to modulate key regulatory systems.

Multi-Target Antagonism and Central Pathway Modulation

The primary function involves the competitive blockade of histamine H1 receptors in both the brain and the periphery. This is complemented by non-selective antagonism at dopamine D2 receptors and muscarinic acetylcholine receptors, particularly within the brainstem. This multi-target engagement modifies the early molecular steps that shape systemic physiological outcomes, leading to CNS depression and suppression of the emetic reflex arc.

Emetic Reflex and Peripheral Physiological Response Suppression

The mechanism operates in systems characterized by heightened activity in specific signaling pathways, such as the reflex arc governing nausea and the acute release of inflammatory mediators. By blocking D2 receptors in the Chemoreceptor Trigger Zone (CTZ) and H1 receptors peripherally, Quitazine initiates or suppresses signaling sequences that result in the reduction of excessive mediator activity, leading to modulated autonomic and peripheral responses.

Dosage and Administration Information

Quitazine (promethazine hydrochloride) is administered across multiple official routes to accommodate varying clinical needs. These include the oral route (tablets and syrup), the rectal route (suppositories), and parenteral injection. The preferred parenteral route is deep intramuscular injection; however, administration via the intravenous (IV) route is permitted but requires specialized preparation. Intravenous delivery must be conducted with the solution diluted to a concentration of 25 mg/mL or less, infused through a large vein, and administered at a rate that does not exceed 25 mg per minute.

Dosing regimens are highly dependent on the context of use, ranging from 12.5 mg to 50 mg for a single adult dose. For long-term usage, such as allergy relief, the drug is commonly scheduled as a single 25 mg dose taken once daily at bedtime. Conversely, for the control of acute conditions, doses may be repeated every 4 to 6 hours, as specified by regulatory guidelines. When taken orally, the medication can be administered with food, water, or milk.

A critical usage restriction is the absolute prohibition for pediatric patients under the age of two years. For children 2 years and older, the administration principle is to use the lowest effective dose. Furthermore, the label requires that when Quitazine is used as an adjunctive sedative, the doses of any concomitant central nervous system depressants, such as narcotics, must be reduced accordingly.

Recent Clinical Evidence

Quitazine: Recent Clinical Evidence

Quitazine (Cytisinicline) is a plant-derived nicotinic acetylcholine receptor partial agonist studied for smoking cessation. It has been used in parts of Europe for decades and is currently undergoing clinical investigation for broader availability.

Efficacy in Smoking Cessation

Clinical trials, including large-scale, randomized, placebo-controlled studies, have evaluated Quitazine's ability to support continuous smoking abstinence in adults who smoke daily and wish to quit. These studies typically provide behavioral support to all participants.

  • Short-Term Outcomes: In a 12-week treatment course, one major Phase 3 trial reported that participants receiving Quitazine achieved significantly higher rates of biochemically confirmed continuous abstinence during the final four weeks of treatment compared to the placebo group. The rates were also significantly higher for a 6-week course compared to placebo.
  • Sustained Abstinence: Follow-up data from this trial suggested that the continuous abstinence rates remained statistically significantly higher for those who completed the 12-week course compared to placebo through six months (Week 9 to Week 24).

Comparative Findings

Research has also compared Quitazine to other established smoking cessation pharmacotherapies:

  • Versus Nicotine Replacement Therapy (NRT): Some trials have reported that Quitazine resulted in superior continuous abstinence rates at six months when compared with a single form of NRT (patch, gum, or lozenge) combined with brief behavioral support.
  • Versus Varenicline: Head-to-head trials comparing Quitazine to varenicline have yielded mixed or inconclusive results regarding their long-term efficacy difference in quit rates, often complicated by differences in dosing schedules and treatment duration used for Quitazine.

Overall evidence suggests Quitazine is associated with an increased likelihood of achieving smoking abstinence compared to not using medication, with the greatest benefit observed when combined with behavioral support.

Frequently Asked Questions (FAQ)

Common questions about Quitazine (FAQ)

Q: Does this medicine interact with my heart medication?

Official product information for Quitazine includes a specific section that details known and clinically important drug interactions. This section provides instructions for healthcare providers on how to manage or mitigate these interactions when Quitazine is used alongside other medicines, including heart medications. Reviewing the 'Interactions with other medicines and products' section or consulting a healthcare professional is recommended to check for specific risks with your prescribed treatments.

Q: Does this medicine make you tired or sleepy?

Official regulatory documents list all common and clinically significant adverse reactions associated with Quitazine use. This information indicates that the medicine may cause effects on the nervous system, such as somnolence (sleepiness) or fatigue. Patients should review the detailed list of possible effects in the 'Possible side effects and safety information' section of the product information.

Q: Is this medicine safe to use if I am pregnant?

Regulatory documents explicitly provide information regarding the potential risks of using Quitazine during pregnancy. This information, found under the 'Use in Specific Populations' section, is intended to guide healthcare providers and patients in weighing the benefits and potential risks. This information is intended to guide conversations with a healthcare professional, as it does not substitute for medical advice regarding an individual's specific health situation.

Q: Can I drink alcohol while taking this medication?

Official labeling contains specific warnings or precautions regarding the concurrent use of Quitazine and alcohol. These statements address any known interactions or potential for increased adverse effects when the two are combined. It is advisable to review the 'Interactions with other medicines and products' or 'Warnings' sections for required safety statements on concurrent alcohol use.

Q: How should I store the tablets?

The official product information details the required storage conditions for Quitazine tablets. This typically includes the acceptable temperature range (e.g., storing below a specific temperature) and the need for protection from moisture or light. These storage instructions are provided to help maintain the medicine's intended quality and shelf life.

How should Quitazine be stored and disposed of?

The official storage and disposal requirements for Quitazine (Promethazine) are defined by government regulatory documents to maintain drug stability and ensure public safety.

Storage Requirements

Condition Requirement (Official Labeling)
Temperature Store at Controlled Room Temperature, typically 20^circ-25 C (68^circ-77 F), and Keep from freezing.
Protection Must be Protected from light and stored away from moisture.
Container Keep the medicine in its original container, which must be tightly closed to prevent exposure to air and light.
Child Safety Keep out of the sight and reach of children and store the medicine locked up.
Stability Note The solution should be inspected before use and discarded if it has developed color or contains a precipitate.

Disposal Instructions

Official disposal mandates require that unused, expired, or unwanted Quitazine must not be flushed into the sanitary sewer system or released to the environment.

Disposal should be done according to local, regional, and national regulations, which often involves returning the product to a pharmaceutical take-back program or pharmacy.

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

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