Marelin

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Marelin

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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 Marelin

Quick Facts

Property Description
Active ingredient Dronabinol (Synthetic Delta^9-THC)
Form Soft capsule or Oral solution
Pharmacological class Cannabinoid
General purpose Appetite stimulant and Anti-nausea agent
Origin Synthetic (Lab-manufactured)

What Type of Medicine is Dronabinol (Marelin)?

Dronabinol is a synthetic medicine belonging to the pharmacological class of cannabinoids. Its active ingredient is a purified, lab-manufactured version of delta-9-tetrahydrocannabinol (Delta^9-THC), which is the principal psychoactive compound found naturally in the Cannabis plant. This manufacturing process ensures Dronabinol is a single, isolated molecule, providing a precise and standardized concentration of the compound in every dose, unlike whole-plant extracts.

Composition and Forms of Dronabinol

This medication is formulated for oral administration, primarily available as a soft gelatin capsule or a clear liquid solution. The active ingredient is dissolved into an oil base (such as sesame oil, which is noted in its formulation) within these oral forms because the drug itself is insoluble in water. This composition is vital for the drug to be properly absorbed through the digestive system. The capsule form was the first approved oral form (Marinol), while the liquid solution (Syndros) was later developed to offer an alternative, often for patients with difficulty swallowing capsules.

What is the General Role of Dronabinol?

The general role of Dronabinol is to modulate the body's internal systems that control appetite and the feeling of sickness. It works by interacting with specific cannabinoid receptors in the central nervous system, which are involved in regulating various bodily functions. This type of cannabinoid is recognized for its ability to help lessen severe nausea and encourage appetite stimulation. Its therapeutic approach is often used when a patient has not found adequate relief from conventional anti-sickness or appetite-stimulating medications.

What side effects are possible with Marelin?

Possible Side Effects and Safety Information

This section outlines the officially documented adverse reactions and safety characteristics of Dronabinol (Marelin) as classified in government regulatory sources, such as the U.S. Food and Drug Administration (FDA) prescribing information.


Adverse Reaction Scope

Category Description
Key adverse reaction categories Neuropsychiatric, Central Nervous System (CNS), Gastrointestinal, and Cardiovascular effects.
Frequency classification Most common reactions ( 3%): Dizziness, euphoria, somnolence, abnormal thinking, abdominal pain, nausea, vomiting, and paranoid reaction.
System-organ classes involved Nervous System Disorders, Psychiatric Disorders, Gastrointestinal Disorders, and Cardiac Disorders.
Serious adverse reactions Officially documented serious risks include Neuropsychiatric Adverse Reactions (e.g., exacerbation of mania, depression, or schizophrenia), Hemodynamic Instability (e.g., hypotension, tachycardia, syncope), and Seizures/Seizure-like Activity.
Population-specific safety Geriatric Patients may show increased sensitivity to the neurological and psychoactive effects. Pregnant/Lactating Women are advised against use, with specific instructions for cessation during and after treatment.
Dose- or exposure-related patterns CNS adverse reactions (e.g., dizziness, euphoria) are classified as dose-related and are often reported to resolve within the first few days of treatment.
Safety-related limitations Contraindicated in patients with a known hypersensitivity to Dronabinol or sesame oil (in the capsule form). Caution is advised regarding co-administration with other CNS depressants due to increased additive effects.

Safety Classifications (High-Level)

Element Description
Regulatory frequency framework The FDA labeling uses the classification of "Most common adverse reactions ( 3%)" to define frequently observed effects in clinical trials.
Context-of-use safety notes The label explicitly notes the potential for Paradoxical Nausea, Vomiting, or Abdominal Pain, which may require dose reduction or discontinuation.

Resulting Safety Structure

  • The most frequently reported adverse reactions affect the CNS and Psychiatric systems, including dizziness, somnolence, and euphoria.
  • Regulatory warnings highlight the potential for serious adverse reactions such as the worsening of existing psychiatric conditions, hemodynamic instability, and seizures.
  • CNS effects are officially recognized as being dose-related and more common when starting therapy.
  • Official constraints note an increased sensitivity and risk for adverse effects in the geriatric population.
  • High-level caution is advised regarding the concomitant use of Dronabinol with other CNS-depressing substances.

Connection to the overall safety profile:

The official safety information structures the understanding of Marelin's risk profile by establishing that effects on the central nervous system are the most frequently observed and defining specific, serious psychiatric and cardiovascular reactions as documented concerns. This framework emphasizes that many common effects are linked to treatment timing and dose, while also identifying special populations, such as older adults, who are officially recognized as having increased sensitivity. The profile is strictly descriptive of the factual classifications published by regulatory authorities, without providing any clinical or prescriptive judgment.

Overdose and Emergency Response

Overdose and when to seek help

Overdose with Marelin is officially documented to involve a spectrum of effects predominantly affecting the central nervous system (CNS) and the cardiovascular system. The documented manifestations are critical for defining when emergency help must be sought.

Documented Manifestations

Regulatory documents describe a range of signs including CNS Effects such as somnolence, slurred speech, confusion, euphoria, and memory impairment. Cardiovascular changes include tachycardia (elevated heart rate) and orthostatic hypotension (blood pressure drop upon standing). General effects include conjunctival injection (reddening of eyes) and symptoms like urinary retention and decreased bowel motility.

Severe Outcomes and Required Action

Severe manifestations documented in official labeling include acute psychosis, delusions, and life-threatening seizures. The regulatory guidance requires that any suspected overdose or over-exposure necessitates calling the Poison Control Center or seeking immediate emergency medical attention. If a seizure occurs, regulatory information states the medication must be discontinued immediately.

Supportive Management

Management of Marelin overdose is symptomatic and supportive, as official sources state that no specific antidote is known. Required procedures include monitoring for hemodynamic changes (heart rate and blood pressure). Elderly patients are officially noted to exhibit increased sensitivity to the neurological and psychoactive effects.

Therapeutic Uses of Marelin

What Marelin Treats: Main Uses and Benefits

The medication is applied across domains where additional symptomatic support is needed, in situations involving symptomatic discomfort and systemic imbalance. The medication is applied in addressing symptoms related to severe nausea and vomiting associated with cancer chemotherapy, and to stimulate appetite in individuals experiencing a significant symptomatic burden of appetite loss and related weight decline.

In settings marked by increased discomfort or tension, Marelin is relevant for easing distress and may contribute to improved comfort. It is commonly used when short-term symptomatic assistance is needed, helping to address symptoms that create noticeable physiological strain. It is helpful in situations where multiple symptoms occur together, and may support general well-being during symptomatic phases.

“This supportive relief is relevant for managing symptoms that interfere with daily comfort and may assist with maintaining functional stability.”


Quick Fact: Support for Symptomatic Nausea

The medication helps address symptom clusters that may become intense or disruptive.

Eligibility and Restrictions for Use

The eligibility for using Marelin (Dronabinol) is strictly defined by regulatory documents, distinguishing between approved adult populations, absolute contraindications, and groups requiring special caution or exclusion.

Eligibility Scope

Category Official Regulatory Statement
Populations Allowed Adults (18 years and older) with no documented contraindications.
Populations Contraindicated Hypersensitivity to Dronabinol or any component of the formulation (e.g., sesame oil for capsules). Patients receiving Disulfiram or Metronidazole (contraindication specific to the oral solution) [FDA Label].
Age-Related Rules Pediatric Use is not established; safety and efficacy in patients under 18 years are not recommended. Older Adults require use with caution due to increased sensitivity to neurological effects [FDA Label].
Pregnancy/Lactation Pregnancy: Use should be avoided as it may cause fetal harm. Lactation: Not recommended; patients should avoid breastfeeding during treatment and for a period after the last dose [FDA Label].

Eligibility-Related Restrictions

Official labeling mandates caution or restricted use for certain adult populations with pre-existing conditions, due to the drug’s potential effects. This includes patients with a history of seizure disorders, cardiac disorders (e.g., hypertension, tachycardia), or a history of substance abuse [NIH StatPearls]. Caution is also advised in patients with a history of psychiatric disorders (e.g., mania, depression, schizophrenia), where use is generally avoided [FDA Label].

Connection to the Overall Eligibility Profile

Regulatory documents establish who is eligible by clearly stating populations where use is contraindicated (due to allergy or drug interaction) or not established (pediatric age groups). Use in the standard adult population is conditioned on the absence of specific historical or physiological issues, placing individuals with seizure disorders or psychiatric histories into a use with caution category, thereby defining the official boundaries of appropriate use.

What should I know about interactions with other medicines?

Marelin (macimorelin) can interact with various other medicines, over-the-counter products, and certain foods, potentially altering its effect or increasing the risk of side effects. It is critical to inform your healthcare provider of all current and planned medications, including prescription, non-prescription, herbal products, and supplements.

Major Drug-Drug Interactions

Particular caution is advised when Marelin is used with medicines that affect the QT interval, which is a measure of heart rhythm. Combining Marelin with other QT-prolonging drugs can increase the risk of serious heart rhythm abnormalities (arrhythmias). Examples of such medications include, but are not limited to, certain antiarrhythmics (e.g., amiodarone, quinidine), antipsychotics (e.g., haloperidol, quetiapine), antidepressants, and some antibiotics (e.g., macrolides, quinolones).

Interaction Type Potential Effect
QT-prolonging drugs Increased risk of serious heart rhythm problems (torsades de pointes)
CYP3A4/5 Inhibitors May increase Marelin exposure and side effects

Other Potential Interactions

Medicines that strongly inhibit certain liver enzymes, particularly cytochrome P450 3A4/5 (CYP3A4/5), may increase the concentration of Marelin in your blood, raising the risk of side effects. Examples of these inhibitors can include certain antifungal agents (e.g., ketoconazole) and HIV protease inhibitors. Discuss the timing of your Marelin dose if you are taking any product known to affect gastric acid secretion, as this may impact absorption. Avoid consuming alcohol while taking this medication, as it may exacerbate potential central nervous system side effects.

Mechanism of Action

Ontology: How Marelin works — Mechanism of Action

Targeted Blockade of Neuronal Signaling

Marelin functions as a reversible, state-dependent inhibitor of Voltage-Gated Sodium Channels ( Na v), primarily the Na v1.7 subtype. Marelin binds to an intracellular site within the channel pore. This interaction limits the necessary influx of sodium ions ( Na^+), a molecular step essential for initiating and propagating an action potential. The inhibition is enhanced when the channel is in the open or inactivated state, which corresponds to conditions of high-frequency neuronal firing.

Modulation of Peripheral Nerve Excitability

This molecular interaction initiates a mechanistic cascade that results in decreased neuronal excitability in peripheral sensory pathways. The failure to generate or sustain action potentials leads to a reduction in afferent sensory signal throughput from the periphery. By intervening early in the signal transmission process, Marelin causes core physiological changes, including a reduced nerve conduction velocity and transient regional desensitization. These mechanistic consequences determine the physiological profile of the drug.

Dosage and Administration Information

How Marelin is Used

Marelin (Dronabinol) is administered via the oral route, available as a soft capsule or a liquid oral solution. The solution form may also be given through a silicone enteral feeding tube. Standardized usage is determined by the patient's indication and involves precise dosing schedules and timing.

For anorexia associated with weight loss, the typical starting dose for capsules is 2.5 mg taken twice daily, one hour before lunch and dinner. The dosage may be gradually increased up to a maximum of 10 mg twice daily. For the nausea and vomiting (N/V) associated with chemotherapy, the initial dose is calculated based on Body Surface Area (BSA) and must be administered on an empty stomach 1 to 3 hours prior to the chemotherapy session. Subsequent doses are taken every 2 to 4 hours, up to six times per day.

Special conditions apply to preparation and patient groups. The oral solution must be measured accurately using the calibrated oral dosing syringe provided and taken with a full glass of water. Capsules must be swallowed whole and not broken or chewed. Furthermore, a lower starting dose is considered for older adults to minimize the risk of central nervous system effects. Dosing adjustments follow a structured titration process, adhering to defined maximum limits for each regimen.

Recent Clinical Evidence

Research evidence / Overview of Studies for Marelin (Dronabinol)

The available research for Marelin (dronabinol) was studied for the clinical situations for which it has been evaluated, primarily relying on evidence from Randomized Controlled Trials (RCTs) and systematic reviews. The following sections summarize what the research explored and what studies monitored in relation to its two approved indications, maintaining a neutral focus on the evidence structure.


Evidence for Use in Appetite Stimulation and Weight Stabilization

The primary research exploring this indication was evaluated in randomized, placebo-controlled trials focused on adults with AIDS who were experiencing weight loss. Researchers examined outcomes related to changes in body weight and stabilization patterns, alongside patient-reported outcomes describing changes in appetite. Studies describe patterns related to symptom measurement where participants receiving the medicine reported higher scores on appetite assessment scales compared to placebo. Research highlights changes measured during the study period that were associated with numerical increases or stabilization patterns in total body weight.


Evidence for Use in Severe Nausea and Vomiting

The primary research for this indication was explored in trials focused on adult cancer patients experiencing severe nausea and vomiting related to chemotherapy. The medicine was studied for use only in patients whose symptoms were refractory (who had not found adequate relief from other therapies). Studies examined the frequency of vomiting episodes and the proportion of patients achieving specific thresholds for measured antiemetic response. Findings were described as conflicting or heterogeneous across different trials.


What Research Gaps and Uncertainty Exist

Scientific reviews have highlighted areas where the evidence base is limited. Comparative evidence is lacking between this medicine and many of the newer antiemetic agents now considered standard of care. Furthermore, certainty remains low on the extent to which reported weight gain in some studies represented an increase in vital lean body mass rather than fat or fluid accumulation. There is limited information for long-term outcomes regarding the sustained effects of the medicine.

Frequently Asked Questions (FAQ)

Common questions about Marelin (FAQ)


Q: How quickly should someone expect Marelin to start working?

A: Official product information describes the initial effects of Marelin as generally starting approximately 30 minutes to one hour after taking the medicine by mouth. The peak effect is described as occurring within two to four hours. The appetite-stimulating effect is described in studies as potentially being sustained for 24 hours or longer after administration.

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

A: Regulatory documents advise caution when Marelin is used alongside other medicines that may prolong the QT interval (affecting heart rhythm) or strongly inhibit certain liver enzymes, such as CYP3A4/5. Official guidance emphasizes informing a healthcare provider of all products being taken, including any over-the-counter medications, to assess potential interactions.

Q: What happens if a dose of Marelin is missed?

A: Official patient information states that if a dose is missed, it should be taken as soon as it is remembered. If it is almost time for the next scheduled dose, the missed dose is advised to be skipped. Official guidance states that double or extra doses should not be taken.

Q: Are there any major food or drink restrictions while taking Marelin?

A: Official labeling advises against the consumption of alcohol while taking this medicine due to the potential to intensify effects on the central nervous system. Product information may also advise against consuming grapefruit or grapefruit juice.

Q: Is Marelin available in different strengths?

A: According to official product information, Marelin is manufactured in multiple strengths. These strengths are noted in the labeling to not be bioequivalent to one another, meaning their effects in the body may differ slightly.

Q: Can Marelin be crushed or split if it is hard to swallow?

A: Regulatory documents state that the soft capsules are to be swallowed whole and should not be broken, crushed, or chewed. If swallowing capsules presents a difficulty, the medicine is also available as a liquid oral solution.

Q: What official information is available about the success rate of Marelin in clinical trials?

A: Research evidence includes measured outcomes related to changes in appetite assessment scores, patterns of total body weight stabilization, and the frequency of vomiting episodes. Official documents note that findings in some studies, particularly for nausea and vomiting, have been described as conflicting or heterogeneous.

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

A: The duration of action for the psychoactive effects is generally described as 4 to 6 hours. However, studies indicate that the medicine’s appetite-stimulating effect may be sustained for 24 hours or longer after a single administration.

Q: Can Marelin interact with herbal supplements?

A: Official information advises patients to inform their healthcare provider about all current and planned medications, including prescription drugs, over-the-counter products, and herbal products or supplements. This is to ensure any potential for interaction can be properly evaluated before starting treatment.

Q: What information should patients share with their doctor before starting Marelin?

A: Regulatory labeling includes a requirement to share information about all current and planned medications, as well as a complete history of certain conditions. This includes any history of seizure disorders, psychiatric conditions, cardiac disorders like hypertension or tachycardia, or substance abuse.

Q: What happens if a potential Marelin side effect is noticed?

A: Official patient information outlines that professional attention is warranted for severe symptoms, as these may be related to serious adverse reactions documented in official sources. Examples include symptoms related to seizures, heart rhythm abnormalities, or significant changes in mental state.

Q: Is Marelin a lifelong medicine or can it be stopped?

A: Official documents describe the pharmacological effects of Marelin as reversible upon cessation of treatment. Official documents state that discontinuing this medicine should only occur under the direction of a healthcare provider.

Q: Does Marelin affect the ability to drive or operate machinery?

A: Yes. Regulatory documents warn that this medicine may impair the mental and/or physical abilities required for operating a motor vehicle or machinery. Official documents include a caution that hazardous tasks should be avoided until an individual knows how the medicine affects them.

Q: Is Marelin generally well-tolerated?

A: The safety profile is structured by a list of common adverse reactions (ge 3%), which primarily affect the central nervous system. The official list also details serious, but less frequent, reactions that require professional caution.

Q: Does Marelin cause weight gain or weight loss?

A: Marelin has an approved indication as an appetite stimulant. For its use in anorexia associated with weight loss, research has shown that patients using the medicine reported numerical increases or stabilization patterns in total body weight.

Q: Is it possible to develop a tolerance to Marelin over time?

A: Official product information describes the development of tolerance and tachyphylaxis (a rapidly diminishing response) to some of the drug’s cardiovascular and central nervous system effects with chronic use. However, tolerance is not reported to develop to the appetite stimulant effect.

Q: Why might a doctor switch a patient from another medicine to Marelin?

A: The medicine’s indication for nausea and vomiting is specifically for adult patients who have failed to respond adequately to conventional antiemetic treatments. This means its use is intended for patients whose symptoms were refractory to standard therapies.

How should Marelin be stored and disposed of?

Marelin's official regulatory labeling specifies strict conditions for storage, stability, and disposal, which vary slightly by formulation (capsule or oral solution).

Storage Classification Capsules Oral Solution
Temperature Controlled room temp (20 C to 25 C) Controlled room temp (20 C to 25 C)
Prohibited Do not freeze. Do not refrigerate or freeze.
Protection Store in a tightly closed container. Protect from light and excessive heat.
Stability (In-Use) Discard after expiration date. Discard 6 weeks after first opening.

All forms must be kept out of the sight and reach of children and stored in a safe place to prevent misuse. As a controlled substance, disposal of unused or expired product must follow official protocols, such as using a drug take-back program, rather than flushing or discarding in household trash.

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

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