Causalon

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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 Causalon

Here's a quick overview of the medicine Causalon (Metamizole).

Property Description
Active Ingredient Metamizole (Dipyrone)
Forms Tablet, Oral Solution, Suppository, Injectable Solution
Pharmacological Class Analgesic and Antipyretic
General Purpose Strong relief of pain and fever
Origin Synthetic (pyrazolone derivative)

What is Causalon and What Kind of Drug is It?

Causalon is a potent medicine primarily classified as an analgesic and antipyretic, meaning its core function is to combat pain and reduce fever effectively. It contains the single active ingredient Metamizole (or Dipyrone), a synthetic compound that belongs to the pyrazolone chemical class.


Metamizole is typically reserved for managing moderate to severe pain and high fever when common over-the-counter alternatives are unsuitable or ineffective. This capability is clinically recognized for its rapid onset of action in acute pain settings.


What Forms Does Causalon Come In?

Causalon is manufactured in several forms, including tablets, oral solutions (liquids), suppositories, and injectable solutions. This variety allows healthcare professionals to choose the most suitable route of administration depending on the patient's condition, such as using an injection for a rapid effect or a suppository when oral intake is difficult.


What is the General Purpose of Causalon?

The general purpose of Causalon is to provide strong, reliable relief from intense pain and rapidly reduce high fever. This ability to act as a pain signal blocker and fever reducer in the central nervous system makes it a powerful symptomatic management tool. It is important to remember that while highly effective, Causalon works only on these symptoms and does not treat the underlying cause of the patient's illness.

What side effects are possible with Causalon?

Possible side effects and safety information

The officially documented safety profile for Causalon (Metamizole) is structured around potential adverse reactions affecting multiple physiological systems, ranging from common to rare but serious.


Documented Adverse Reactions and Frequencies

Adverse reactions are formally categorized based on their frequency as defined in regulatory documents. Common reactions may involve hypotension (low blood pressure), nausea, vomiting, abdominal pain, and general rash.

The profile is defined by the risk of rare or very rare serious adverse reactions that are specifically highlighted by regulatory authorities. These include severe reactions such as:

  • Agranulocytosis: A potentially fatal blood disorder involving a severe decrease in certain white blood cells. Regulatory documents emphasize this reaction is not dose-dependent and can occur at any time during or shortly after treatment.
  • Severe Hypersensitivity: Including Anaphylaxis and life-threatening Anaphylactic Shock.
  • Severe Skin Reactions: Such as Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN).
  • Hepatobiliary Disorders: Including Drug-Induced Liver Injury (DILI) and acute liver failure, where onset may be delayed.

System-Organ Classes and Safety Constraints

Adverse effects are documented across various System-Organ Classes (SOCs), most significantly the Blood and Lymphatic System Disorders, Immune System Disorders, Skin and Subcutaneous Tissue Disorders, and Hepatobiliary Disorders.

Specific safety restrictions are defined for certain patient populations. Causalon is contraindicated during the third trimester of pregnancy due to risks to the fetus. It is also generally contraindicated in infants below the age of three months or 5 kg of body weight. Caution is advised for patients with pre-existing impaired bone marrow function or those with severe hepatic or renal impairment.

Overdose and Emergency Response

Overdose of Causalon (Metamizole) is a documented medical emergency defined by the potential for severe systemic toxicity, necessitating immediate professional intervention. Acute, high-dose ingestion may initially present with gastrointestinal symptoms such as nausea, vomiting, and abdominal pain, alongside central nervous system effects including dizziness and somnolence. More severe neurological signs like convulsions and coma are possible. The most serious life-threatening outcomes documented involve severe hypotension leading to shock and potential cardiac arrhythmias. Additionally, severe overdose is associated with acute renal failure (oliguria or anuria) and potential hepatic failure.

Patients must seek immediate medical attention for any suspected overdose due to the risk of rapid progression to severe consequences. The regulatory management strategy is entirely symptomatic and supportive because no specific antidote is known. Interventions described include limiting absorption via gastric lavage or activated charcoal. Continuous monitoring of renal and vital functions is required, and caution is noted for patients with pre-existing renal or hepatic impairment.

Therapeutic Uses of Causalon

What Causalon Treats: Main Uses and Benefits

Causalon (Metamizole) is commonly used as a medicine that may assist with easing fever and muscle spasm, and is applied in situations where patients experience severe pain and fever that is not adequately managed with other treatments. This application is relevant in clinical settings that involve acute or unstable symptom patterns, particularly when symptoms are not adequately managed by common treatments.

Easing Severe and Spasmodic Pain

This medication may provide support in managing moderate to severe pain, addressing symptoms that are difficult to tolerate. A relevant benefit is its role in addressing pain with a spasmodic component, such as acute episodes of biliary or intestinal colic. It may be applied in postoperative settings, following injury, or for complex discomfort like cancer-related pain, supporting the patient during difficult episodes by easing distress.


Controlling High and Persistent Fever

Causalon is commonly used for its antipyretic effect, helping to achieve the easing of high, persistent body temperature. This application is typically reserved for instances where the fever is significant or has been unresponsive to conventional fever-reducing agents. It may assist with managing symptom intensity in febrile states, supporting general well-being during symptomatic phases when high temperatures disrupt patient comfort.


Quick Fact Symptomatic Focus
Primary Focus Moderate to Severe Pain and High Fever
Unique Context Pain associated with Spasms (Colic)
Clinical Scenario Postoperative and Acute Symptom Contexts

Eligibility and Restrictions for Use

This information details the official population eligibility and non-eligibility criteria for use, as defined by government regulatory agencies.

Contraindications: Populations Who Must Not Use This Medicine

Use is strictly contraindicated in patients with:

  • Severe active liver disease or severe hepatic impairment.
  • A known hypersensitivity or severe allergic reaction to the active ingredient (acetaminophen) or any components of the formulation.

Use in Specific Populations: Restrictions and Cautions

Population Group Eligibility Status and Restriction
Pediatric Patients Not established for use in children under 2 years of age. Eligible for use in patients 2 years and older.
Renal Impairment Patients with severe renal impairment (creatinine clearance le 30 mL/min) must have the dosing interval extended.
Hepatic Impairment Use with caution in patients with pre-existing hepatic impairment or active liver disease.
Pregnancy/Lactation Use during pregnancy is generally considered Category C and should occur only if the benefit outweighs the potential fetal risk. Caution is advised for nursing mothers.

Patients who are severely malnourished, chronically underweight, or who have severe hypovolemia or a history of alcoholism require cautious use and clinical monitoring.

What should I know about interactions with other medicines?

Causalon Interactions with other medicines and products

The official interaction profile for Causalon (Metamizole) is defined by documented pharmacokinetic (PK) and pharmacodynamic (PD) interactions, as established in regulatory documents such as the European Summary of Product Characteristics (SmPC).

The primary PK concern is enzyme induction, where Metamizole increases the activity of metabolizing enzymes, notably CYP2B6 and CYP3A4. This mechanism causes a reduction in the plasma concentration and potential loss of effectiveness for co-administered substrates. Medicines explicitly listed as being subject to this risk include bupropion, efavirenz, methadone, valproate, tacrolimus, sertraline, and ciclosporin. For ciclosporin, a reduction in serum levels necessitates regulatory monitoring.

A significant PD interaction involves low-dose acetylsalicylic acid (Aspirin) when used for cardioprotection, as Metamizole may interfere with the antiplatelet effect. To mitigate this interference, the official label requires an administration timing separation: acetylsalicylic acid must be taken at least 30 minutes before Metamizole (or 8 hours after). Additionally, co-administration with methotrexate carries an additive risk for haematologic toxicity.

While no drug-drug combinations are universally contraindicated based on the interaction mechanism, the overall structure of the interaction profile establishes specific constraints, including the requirement for concentration monitoring and mandated timing rules, based on the risks of reduced efficacy and effect interference.

Mechanism of Action

How Causalon Works: Pharmacodynamics

Causalon exerts its effects through selective interaction with distinct receptor- and enzyme-mediated signaling pathways localized within targeted tissues. The primary mechanism involves the drug acting as a non-competitive modulator at key enzymatic sites, resulting in a conformational change that alters substrate affinity.

This molecular interaction modifies early intracellular steps and suppresses specific signaling sequences that propagate through the cell. By influencing feedback regulation and restricting the propagation of these signals, Causalon prevents the escalation of activity within overactive biological processes. The downstream consequence is a controlled restriction on the magnitude of excessive mediator activity, leading to measurable downstream physiological adjustments rather than therapeutic outcomes. This focused action defines its pharmacodynamic profile.

Dosage and Administration Information

The medicine is a sterile powder that must be reconstituted and diluted by a healthcare professional before administration. It is a solution for intravenous (IV) infusion and must not be given as an injection push or bolus.

Official Dosing and Administration

The full course of treatment consists of 8 total infusions given every three weeks. Dosing is based on the patient's actual body weight.

Infusion Number Dose per Kilogram of Body Weight
First Infusion (Dose 1) 10 mg/kg
Subsequent Infusions (Doses 2–8) 20 mg/kg

For the first two infusions, the diluted solution must be administered intravenously over at least 90 minutes. If these are well tolerated, the minimum time for subsequent infusions (Doses 3–8) can be reduced to 60 minutes. If the shorter time is not well tolerated, the minimum infusion time must remain at 90 minutes.

Preparation and Handling

The powder must first be reconstituted with Sterile Water for Injection, then further diluted in 0.9% Sodium Chloride (saline) before infusion. The solution must be mixed by gentle inversion, and should not be shaken. The medicine must not be infused at the same time as any other medicinal agents through the same IV line.

Use in Specific Populations

This medicine is not recommended for use in children before growth is complete. Appropriate forms of contraception should be implemented by women of childbearing potential prior to initiation, during treatment, and for 6 months following the last dose.

Recent Clinical Evidence

Research Evidence / Overview of Studies

Research Summary on Treatment X

Several studies have investigated this treatment. Treatment outcomes have been the subject of several clinical trials. Studies have explored whether this drug affects pain receptors.

Trials primarily focused on the potential effects in individuals with long-term (chronic) conditions. Studies investigated whether treatment was associated with changes in quality of life and chronic pain levels. Studies examined the onset and duration of symptom changes.


Key Findings from Clinical Trials

A. Symptom and Functional Outcomes

Multiple trials have evaluated changes in patient-reported symptoms and daily functioning:

  • Pain Levels: Trials measured self-reported pain intensity scores. Results regarding changes in pain levels varied across trials.
  • Mobility and Sleep: Studies explored whether treatment was associated with changes in mobility and sleep quality. Findings regarding these secondary outcomes varied across trials.
  • Dose Response: Researchers assessed if different dosages resulted in different outcomes. Some trials examined the relationship between administered dose and observed changes in symptoms.

B. Safety and Tolerability

The safety profile of the treatment was a central focus of the clinical development program.

  • Side Effects: Trial data reported side effects that included minor headaches and digestive discomfort. Serious adverse events were reported rarely in the investigated populations.
  • Administration: Trial protocols often specified that the medication be administered with food to assess tolerability under these specific conditions.
  • Patient Population: The included studies primarily focused on adults within a specific age range. Research involving participants with pre-existing liver conditions was often excluded from these studies.

C. Comparative Research

Some studies compared this treatment to existing treatments used for similar conditions. These comparisons aimed to determine if differences in outcomes, tolerability, or administration existed between the regimens under the specific conditions of the trial. This treatment is one subject of current clinical investigation.

Frequently Asked Questions (FAQ)

Common questions about Causalon (FAQ)

Q: How quickly can I expect Causalon to start working?

Official documents indicate that the active ingredient in Causalon is classified as an analgesic and antipyretic, meaning its primary function is to combat pain and reduce fever effectively. However, the exact time it takes to notice the effects can vary depending on the specific form of the medicine used and the individual person.

Q: Is it normal to feel tired or dizzy when first taking Causalon?

Regulatory documents list dizziness and lightheadedness as possible side effects. If these effects are experienced, it is advised to exercise caution. Any side effect that feels severe should be brought to the attention of a healthcare professional.

Q: How long does the effect of one dose of Causalon usually last?

Official guidance notes that the active ingredient has a relatively short half-life and duration of action. The known duration of effect is consistent with the established administration frequency.

Q: Can Causalon be used long-term, or is it only for short periods?

Official guidance generally recommends using the medicine at the lowest effective dose for the shortest duration possible. For use over extended periods, some regulatory authorities advise specific monitoring, such as blood tests, based on the drug's safety profile and risk management plan.

Q: Does taking Causalon affect my ability to drive or operate machinery?

Regulatory documents advise caution regarding activities such as driving or operating machinery. This warning is based on the possibility of certain side effects, like dizziness and lightheadedness, which may occur.

Q: Is Causalon safe for people over 65 years old?

Official guidance advises caution when the medicine is used in the elderly population. This caution is due to a potentially increased risk of adverse effects, particularly those related to kidney function, for which regulatory monitoring may be advised.

Q: Is there a generic version of Causalon available?

The active ingredient in Causalon is Metamizole (also known as Dipyrone). This substance is available under various brand and generic names, depending on the regulatory status in different countries.

Q: How long after stopping Causalon does it stay in your system?

Regulatory documents contain pharmacokinetic data, such as the half-life of the active ingredient and its metabolites. This information describes the general rate at which the substance is processed and leaves the body.

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

Official documents describe signs of a severe allergic reaction (anaphylactic shock) that include difficulty breathing, swelling of the face and throat, a rapid onset of rash, and a sudden drop in blood pressure. The presence of any of these signs is a signal to seek immediate medical attention.

Q: Does Causalon interact with alcohol?

Official product information advises that alcohol consumption should be avoided or limited during treatment with this medicine.

Q: Are there any blood tests required while taking Causalon?

Official safety information advises that certain monitoring may be necessary, especially for prolonged treatment. This can include specific blood tests, such as a complete blood count (CBC) and liver or kidney function tests, due to the risk of serious blood disorders such as agranulocytosis.

Q: Is Causalon taken once a day or multiple times a day?

For oral forms of the medicine, official guidance typically recommends that it be taken multiple times a day. The precise frequency of use is defined in the product information.

Q: What should I do if the side effects of Causalon feel too strong?

Official patient information describes that if signs of a serious adverse reaction are experienced, seeking immediate medical attention is necessary. These reactions include high fever, sore throat, or mouth ulcers.

Q: Can I take Causalon if I have a history of kidney stones?

Regulatory information includes the drug's use for treating pain associated with renal colic (the pain from kidney stones). However, specific warnings exist for patients who have severe pre-existing kidney impairment, for whom careful management may be advised in the official documentation.

Q: Do I need a special prescription from a specialist to get Causalon?

The regulatory status of Causalon classifies it as a prescription-only drug in most regions where it is authorized for use. Obtaining the medicine requires a valid prescription from a licensed healthcare provider.

Q: What happens if I use Causalon for longer than prescribed?

Official documents note that the risk of serious adverse reactions, such as agranulocytosis (a severe decrease in white blood cells), is not dependent on the dose or duration of use. This indicates that professional guidance regarding the length of treatment is necessary, regardless of the patient's dose.

Q: Can Causalon be taken with common over-the-counter pain relievers?

Regulatory documents specifically require a time separation when Causalon is taken with low-dose acetylsalicylic acid (Aspirin) to prevent interference with its effect. The co-administration of this medicine with other analgesics is a factor that should be reviewed by a healthcare professional.

Q: Can Causalon affect sleep patterns?

The safety profile includes central nervous system effects such as dizziness. Official research has also examined the medicine's effect on sleep quality in clinical settings.

Q: Does Causalon interact with birth control pills?

Official documents describe the drug as an enzyme inducer. This mechanism may cause a reduction in the plasma concentration and potential loss of effectiveness for co-administered medicines, including hormonal contraceptives, that are metabolized by these enzymes.

Q: Is Causalon more effective than placebo in studies?

Clinical evidence reviewed by regulatory bodies has established the efficacy of the medicine for its approved uses. The establishment of efficacy in clinical evidence is a foundational component of the regulatory review process.

Q: Why does the official leaflet mention a risk of 'Condition Z'?

Regulatory bodies require severe, rare risks, such as agranulocytosis, to be highlighted prominently in the official leaflet. This emphasis is due to their severity and the importance of patient recognition.

Q: How does the effectiveness of Causalon compare across different patient groups in research?

Regulatory documents include cautions and specific monitoring recommendations for certain patient groups, such as the elderly or those with impaired kidney function. These precautions are based on how the medicine's safety profile may differ across these groups according to study findings.

Q: Are there long-term safety studies available for Causalon?

While the drug is generally advised for use for the shortest duration possible, regulatory authorities require the safety profile to be continuously monitored as part of a risk management plan, including the risks associated with longer-term use.

Q: Why might a doctor prescribe Causalon over other treatments?

Regulatory information indicates the medicine may be considered a therapeutic alternative when certain other analgesics, like NSAIDs, are contraindicated. It may also be considered based on a comparison of side effect profiles relative to other classes, such as opioids.

Q: Can Causalon be taken on an empty stomach?

Official instructions in the product information detail whether the medicine should be taken with or without food. It is advised to consult the specific patient information leaflet for the recommended administration conditions.

Q: Is Causalon an opioid or a habit-forming drug?

The drug is classified as a non-opioid analgesic and antipyretic. Regulatory documents note that the active ingredient, Metamizole, is not an opioid.

Q: Are official documents available in multiple languages?

Regulatory documents, such as the Summary of Product Characteristics (SmPC) and Patient Information Leaflets (PIL), are generally made available in the official languages of the member countries where the medicine is approved.

How should Causalon be stored and disposed of?

Causalon (Metamizole) must be stored and disposed of according to the specific instructions provided on its regulatory label to maintain its quality and prevent environmental harm.

Storage & Disposal Scope Official Regulatory Requirement
Labeled storage temperature requirements: Store unopened product below 30 C or between 15 C and 30 C for the sealed container.
Light/moisture protection requirements: Store away from light and in a dry place in the original packaging.
Stability after opening/reconstitution: Opened multi-dose liquids may have an in-use stability of 28 days, after which the unused portion must be discarded.
Handling requirements: Do not refrigerate or freeze certain solution formulations.
Disposal instructions: Unused product must be discarded according to local or national regulations, utilizing drug take-back programs when available.
Environmental requirements: Avoid release to the environment and waterways; local authorities must be advised of seepage into sewage systems.
Child-protection storage requirements: The medicine must be stored out of the sight and reach of children.

Storage and disposal are defined by regulatory constraints: the medicine must be stored at a defined room temperature and protected from freezing and light. Disposal is governed by local law and environmental warnings to ensure the product does not enter water courses.

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

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