Aculoid

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Aculoid

Medically reviewed

Marina Burgos

Last updated on 10/01/2026

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 Aculoid

What is Aculoid? An Overview of Cyclizine

Property Description
Active Ingredient Cyclizine
Form Tablet, Injection Solution, Suppository
Pharmacological Class Antihistamine (H₁-Antagonist), Antiemetic
General Purpose Relief of Nausea, Vomiting, and Dizziness
Origin Synthetic organic compound

What Type of Medicine is Aculoid (Cyclizine)?

Aculoid is a medication whose active component is Cyclizine, a synthetic organic compound derived from the piperazine chemical structure. It is formally classified as an antihistamine drug, specifically belonging to the H₁-receptor antagonist group, and is further characterized as an anticholinergic antiemetic. The drug’s classification highlights its unique ability to influence the central nervous system, which is crucial for controlling motion sickness and balance disturbances. Its therapeutic role is widely accepted, with Cyclizine being included on the World Health Organization’s (WHO) Model List of Essential Medicines for the management of nausea and vomiting.


The Composition and Physical Forms of Aculoid

The medicine is a single active ingredient product containing Cyclizine, typically prepared as the hydrochloride or lactate salt. The form varies based on the intended route of administration. Aculoid is supplied in several high-level dosage forms, including oral tablets and a sterile solution for injection suitable for parenteral administration. Cyclizine formulations have been clinically recognized for their rapid onset of action in managing motion sickness, a differentiating factor often noted in pharmacological studies. The choice between the hydrochloride or lactate salt is primarily based on the excipient, as the lactate salt is frequently dissolved in the sterile liquid vehicle used for injections.


What is the General Purpose of Aculoid?

The general purpose of Aculoid is to act as an antiemetic (anti-sickness) and antivertigo medicine, providing relief from discomfort related to motion and balance disturbances. By acting on specific receptors in the brain and depressing the excitability of the labyrinthine apparatus (the inner ear's balance organ), the medication helps manage feelings of nausea, vomiting, and dizziness. Cyclizine effectively addresses typical situations, such as preventing feelings of sickness during prolonged travel by car or boat. This makes its core benefit the rapid and effective management of sickness and unsteadiness, particularly those symptoms associated with motion sickness or episodes of vertigo.

Regulatory References

  1. WHO Model Lists of Essential Medicines

What side effects are possible with Aculoid?

Possible Side Effects and Safety Information

The safety profile of Aculoid (Cyclizine) is formally classified by regulatory authorities based on the system-organ class affected and the frequency of occurrence documented in clinical use. Common adverse reactions listed in official documents include drowsiness, dry mouth, constipation, and blurred vision.


Documented Adverse Reaction Groupings

Adverse effects are categorized into groups reflecting the body systems involved, known as System-Organ Classes (SOCs). Key systems noted in the regulatory documents are Nervous System Disorders (e.g., somnolence, headache, incoordination), Gastrointestinal Disorders, Psychiatric Disorders (e.g., disorientation, hallucinations), and Cardiac Disorders (e.g., tachycardia, palpitations).

Many specific, systemic adverse reactions, including rare events, are often formally categorized as Frequency Not Known (cannot be estimated from the available data) in regulatory summaries.


Serious Adverse Reactions and Special Safety Constraints

The regulatory profile also documents rare but clinically significant reactions. Serious adverse reactions noted in official labeling include anaphylaxis, convulsions (seizures), agranulocytosis (a blood disorder), and specific types of hepatic dysfunction (liver problems) such as cholestatic hepatitis. Cases of paralysis have also been reported with intravenous use.

Caution is officially advised for use in individuals with certain pre-existing conditions, including glaucoma, conditions leading to urinary retention (such as prostatic hypertrophy), obstructive gastrointestinal disease, and hepatic disease. Furthermore, regulatory information notes the potential for abuse or misuse for euphoric or hallucinatory effects and states that hallucinations are explicitly linked to situations where dosage recommendations have been exceeded.

Overdose and Emergency Response

Overdose and when to seek help

Aculoid is a potent medication with a defined risk profile for overdose, which may lead to serious harm or death. The primary risk is related to severe respiratory depression caused by effects on the Central Nervous System (CNS).

Overdose Risks

Overdose Factor Description (Official Regulatory Basis)
Increased Dose Risk of overdose is significantly increased with higher prescribed doses.
Product Type Extended-release products carry a greater risk for overdose and death due to the larger amount of active substance present.
Misuse Crushing or dissolving the tablet, particularly for injection, could result in a rapid and potentially lethal overdose.

Required Emergency Actions

Immediate medical attention is required in any situation where an overdose is suspected. Due to the high risk of serious outcomes, patients, caregivers, and prescribers should discuss the availability and use of an opioid overdose reversal agent, such as naloxone or nalmefene.

The presence of an overdose reversal agent is a necessary precautionary measure to have readily available for emergency situations involving accidental exposure, misuse, or suspected overdose to potentially reverse the life-threatening effects of respiratory depression.

Therapeutic Uses of Aculoid

Aculoid (Cyclizine) is used to provide symptomatic relief by addressing symptom clusters related to systemic imbalance and heightened physiological activity, which supports patients during difficult episodes.

Managing Motion and Travel Sickness

Aculoid is commonly used for the prevention and management of motion sickness, which manifests as a cluster of symptoms including nausea, vomiting, and lightheadedness triggered by movement. The medication is applied when appropriate for this purpose for relevant patient groups, in alignment with official prescribing guidance. It is often used as a prophylactic measure before travel to provide symptomatic support and contribute to improved comfort and stability during prolonged periods.

Easing Vestibular Vertigo and Unsteadiness

The medication is relevant for easing acute and episodic balance disturbances, such as the intense, spinning sensation of vertigo associated with conditions like Menière's Disease. It helps to moderate these pronounced vestibular symptoms, offering the therapeutic benefit of reducing the symptom burden and supports patients during episodes of heightened discomfort and unsteadiness.

Supportive Control of Clinical and Post-Surgical Nausea

Aculoid provides supportive relief for sickness arising in specific clinical contexts, including the management of Post-Operative Nausea and Vomiting (PONV) and nausea induced by certain necessary treatments, such as narcotic analgesics or radiotherapy. This symptomatic assistance contributes to easing the overall symptom load during these phases.


Quick Fact: Relief for Nausea and Dizziness

Aculoid provides supportive assistance by addressing the dual distress of sickness (nausea/vomiting) and unsteadiness (vertigo/dizziness), thereby assisting with supporting functional stability in acute scenarios.

Eligibility and Restrictions for Use

Who can and cannot use Aculoid?

The eligibility for using Aculoid (Cyclizine) is strictly defined by regulatory labeling based on patient health status and age.

Aculoid Must Not Be Used (Contraindications):

Use is absolutely prohibited in patients with a known hypersensitivity (allergy) to Cyclizine or any excipient. It is also contraindicated in individuals with acute alcohol intoxication and, by some regulatory standards, in those with severe heart failure. Use should generally be avoided in patients with porphyria.

Conditional Use and Caution Required:

Aculoid must be used with caution and close monitoring in patients with pre-existing conditions, as the drug may worsen them. These conditions include glaucoma, conditions leading to urinary retention, obstructive disease of the gastrointestinal tract, and epilepsy (or conditions causing seizures). Use is also conditional in patients with hepatic disease (liver impairment).

Age and Special Population Eligibility:

  • Adults are generally eligible for standard use.
  • Children eligibility for oral tablets is restricted to those aged 6 years and over. Use is not recommended below this age, and the injectable form's safety is not established in the pediatric population.
  • Use is generally not recommended during pregnancy or when breastfeeding, as Cyclizine is known to be excreted in human milk.

What should I know about interactions with other medicines?

Interactions with other medicines and products

The official regulatory profile for Aculoid (Cyclizine) is characterized by clinically significant pharmacodynamic interactions, primarily involving additive effects on the central nervous system (CNS) and potentiation of anticholinergic activity.

Classification Documented Interaction Statement
Contraindicated Combination Acute alcohol intoxication is formally prohibited for co-administration. This restriction exists because the anti-emetic properties of Cyclizine may conceal the progression of toxic effects arising from acute alcohol exposure.
Additive CNS Depressant Effects Co-administration with other CNS depressants (such as hypnotics, tranquillisers, anaesthetics, antipsychotics, and barbiturates) may result in enhanced soporific effects and general CNS depression. The official labeling specifies that this additive sedating effect also occurs with the opioid Pethidine. Furthermore, the co-administration of Cyclizine with certain Opioid Analgesics may counteract their haemodynamic benefits.
Additive Anticholinergic Action Concomitant use with other anticholinergic drugs (including Tricyclic Antidepressants and Monoamine Oxidase Inhibitors) is associated with an increased risk due to additive antimuscarinic action across the body.
Masking of Signs Use with ototoxic drugs (such as aminoglycoside antibacterials) may mask the early warning signs of damage caused by the ototoxic agent, as the anti-vertigo effect can conceal symptoms like dizziness or tinnitus.

The interaction structure is defined by official government documents which classify the resultant pharmacodynamic changes upon co-administration. These regulatory constraints primarily highlight the potential for enhanced sedation and systemic antimuscarinic effects, guiding official restrictions on concomitant use with specific drug classes.

Mechanism of Action

Aculoid is a piperazine-derivative compound that functions as a first-generation histamine H1 receptor antagonist. Its primary molecular interaction is the competitive antagonism of H1 receptors, particularly within the central nervous system (CNS).

This antagonism prevents the endogenous neurotransmitter histamine from binding to and activating the H1 receptor, thereby modulating histaminergic signaling. Aculoid also exhibits anticholinergic (antimuscarinic) properties, resulting in the non-selective blockade of central muscarinic acetylcholine receptors ( mAChR).

The compound is hypothesized to exert its functional effects by acting on the vestibular nuclei and the chemoreceptor trigger zone ( CTZ) in the medulla. H1 and mAChR blockade in these areas reduces the excitability of the labyrinthine apparatus, which modulates signals transmitted to the emetic center. This cascade results in a systemic depression of vestibulocochlear nerve activity and reduced central nervous system responsiveness to motion-related stimuli.

Dosage and Administration Information

Aculoid (Cyclizine) is administered through three officially approved routes: the oral route using the 50 mg tablet, and the parenteral routes, which include intramuscular (IM) and intravenous (IV) injection, typically reserved for clinical settings. The medicine is used based on a standard adult unit of 50 mg per single administration.

Dosing regimens permit administration up to three times a day (TID), ensuring appropriate spacing between doses, usually in intervals of approximately eight hours. The total intake across a 24-hour period must not exceed the 150 mg maximum daily dose established by regulatory authorities.

For prophylactic use, the initial 50 mg oral dose is taken 1 to 2 hours prior to the onset of travel. Oral doses may be taken with or without food. When the intravenous form is necessary, it requires a slow administration over a minimum duration of three to five minutes; the injection solution may be diluted with standard intravenous fluids to achieve this rate.

The official instructions include specific age-based adjustments. Adolescents (age 12 years and older) follow the adult regimen. For children between the ages of 6 and 12 years, the official oral dose is a lower 25 mg, which can also be repeated up to three times daily. Use in patients with hepatic impairment requires caution.

Recent Clinical Evidence

Research Evidence for Aculoid (Cyclizine): Overview of Studies

Research exploring Aculoid (Cyclizine) has centered on studies involving acute or disruptive episodes, particularly those related to physical discomfort and systemic or functional imbalance. This section describes the types of research that have been conducted and what the findings reported, without giving any clinical advice.


Evidence for Use in Motion Sickness Prevention and Management

Aculoid was studied for motion sickness using various research designs, including short-term Randomized Controlled Trials (RCTs), Human Performance Studies, and pharmacological investigations. This body of research primarily included healthy adults observed in settings such as sea travel or motion simulations. outcomes related to physical discomfort were monitored, including the measurement of nausea, vomiting, and lightheadedness over defined time intervals related to travel.

This research contributes to the broader evidence landscape, and research highlights changes measured only during the immediate exposure period. The evidence level classification for this use is High.

However, many of the foundational studies are older, meaning they may not meet the methodological standards of modern trials. There is limited information for long-term outcomes or sustained use beyond the acute travel phase. While regulatory summaries mention use in children aged 6 and older, dedicated data for these specific groups remains insufficient compared to the adult populations studied.


Evidence for Use in Managing Post-Operative Nausea and Vomiting (PONV)

Research exploring this area includes Randomized Controlled Trials (RCTs) and Systematic Reviews/Meta-analyses. These studies were conducted during periods of increased symptom activity following surgery, focusing on adult surgical patients where outcomes related to episodic or acute changes were tracked.

The studies monitored outcomes capturing phases of heightened symptom activity, such as the incidence and severity of nausea and vomiting, within the immediate le 24 hours post-operation. Research describes patterns related to the need for supplemental medications (rescue antiemetics) during this acute phase. The evidence level classification for this context is Moderate to High.


Studies in Specific Patient Groups (Special Populations)

The primary populations included in the core research are healthy adults and adult surgical patients. While children (aged ge 6 years) may be included in some use summaries for motion sickness, the data for certain groups remain insufficient compared to the general adult population. There is limited information detailing specific research patterns for older adults experiencing dizziness or those with complex co-existing health conditions. Research does not determine whether an individual will respond similarly, and results apply only to the populations studied within the trial protocols.


Long-Term Studies, Follow-up Durations, and Data Gaps

The majority of research for Aculoid was observed in contexts related to episodic or acute changes, meaning the follow-up durations were limited and short-term. Studies tracked outcomes over periods ranging from a few hours to le 24 hours for acute symptoms. Research provides insight into short-term changes but long-term effects are not fully established for chronic or maintenance use. Overall, comparative evidence is lacking for certain indications, and sample sizes were modest in some of the older trials. These limitations indicate that while short-term symptom patterns have been widely observed, research is ongoing in the broader evidence landscape to fully characterize all outcomes.

Key Studies & References

  1. Cyclizine Monograph (General Purpose and Classification)

Frequently Asked Questions (FAQ)

Common questions about Aculoid (FAQ)

Q: How quickly does Aculoid usually start to have an effect?

Official health guidance states that Aculoid typically begins to work relatively quickly after administration. According to available information, the medicine starts to have an effect approximately 30 minutes after being taken.


Q: Is it common to feel tired when taking Aculoid?

Yes, official regulatory documents list drowsiness as a common adverse reaction. Aculoid is formally classified as a sedating antihistamine, meaning it belongs to a group of medicines known to produce feelings of sleepiness or tiredness.


Q: Why does the Aculoid package have a specific warning about certain foods?

The oral tablet form of Aculoid may be taken with or without food, as described in official documents. However, official labeling highlights specific restrictions regarding the use of alcohol. Concomitant use with alcohol is formally prohibited due to the potential for enhanced central nervous system (CNS) side effects.


Q: What is the expected duration of effect after a single dose of Aculoid?

Studies and official information indicate that the effect of a single dose of Aculoid is relatively long-lasting. The duration of effect is generally described as continuing for approximately 4 to 6 hours.


Q: Can Aculoid be taken with vitamins or herbal supplements?

Regulatory constraints primarily focus on specific drug-to-drug interactions documented in clinical trials. Because comprehensive data on all herbal or vitamin supplements may not be present in official labels, patients are typically instructed to discuss their full list of medications and supplements with their prescriber.


Q: Is it true that Aculoid is only for short-term use?

Official research for Aculoid has been observed primarily in contexts related to acute and short-term symptom management. Regulatory documents note that information regarding long-term outcomes and sustained effects of the medicine is limited in the current evidence landscape.


Q: What specific laboratory tests are sometimes needed for people taking Aculoid?

Official safety profiles document rare but clinically significant adverse reactions involving hepatic dysfunction (liver problems). Due to this documented risk, patients with hepatic concerns may undergo evaluation that includes checking liver function.


Q: Does taking Aculoid with or without food change how it is absorbed?

The official product characteristics allow the oral tablet form of Aculoid to be taken with or without food. This is the condition of use described in regulatory documents.


Q: Are there different brand names for the medicine Aculoid?

Yes, the active ingredient in Aculoid is Cyclizine. This active component is marketed under various trade names in different countries globally, which may include names such as Valoid or Marezine.


Q: Can people with kidney conditions use Aculoid?

Official drug profiles include renal disease (kidney disease) as a condition that requires consideration. This is due to the potential for increased patient sensitivity to the drug's anticholinergic effects.


Q: Is Aculoid addictive or habit-forming?

Regulatory safety information does document the potential for abuse or misuse for euphoric effects. However, official sources generally indicate that addiction is unlikely when the drug is used under typical conditions.


Q: What official source defines the approved uses of Aculoid?

The approved uses, contraindications, and safety information for Aculoid are formally defined in official government documents. These include the FDA Labeling and the EMA Summary of Product Characteristics (SmPC).


Q: Is Aculoid a preventative medication or a treatment for symptoms?

Aculoid is officially authorized and used in both contexts. It is approved for prophylactic use (prevention of motion sickness symptoms before they start) and also for the treatment of existing symptoms such as nausea and vomiting.


Q: Is Aculoid safe to take with common cold or flu medications?

Official interaction guidance specifies caution regarding co-administration with other medications that belong to the class of CNS depressants or anticholinergics. Taking Aculoid alongside cold or flu medicines that contain these agents may lead to enhanced sedative effects.


Q: Does Aculoid interact with birth control pills?

Official health information states that Cyclizine does not affect the efficacy of contraceptive pills or other forms of hormonal contraception. Regulatory information indicates that Aculoid is not documented to affect the efficacy of these methods.


Q: Does Aculoid affect mood or sleep patterns?

Yes, official adverse reaction labeling documents effects on the central nervous system. These include somnolence (drowsiness) and insomnia under Nervous System Disorders, as well as Psychiatric Disorders such as disorientation and hallucinations.


Q: Is Aculoid a controlled substance?

The active ingredient Cyclizine is generally not classified as a controlled substance by major regulatory agencies. Its legal status is often classified as a Pharmacy Medicine or available Over-the-Counter in certain jurisdictions.


Q: What if I experience a rare or unexpected side effect from Aculoid?

Regulatory bodies maintain official systems for the voluntary reporting of suspected adverse reactions or problems with medicines. These systems include designated reporting programs for patients to submit information about adverse events.


Q: Is Aculoid mentioned in government health guidelines for my condition?

The active ingredient, Cyclizine, is included on the World Health Organization’s (WHO) Model List of Essential Medicines. This list identifies key medications considered necessary for a basic healthcare system.

How should Aculoid be stored and disposed of?

Official Storage Requirements

Regulatory documents define the required conditions to maintain the stability and quality of Aculoid (Cyclizine). The medicine must be stored below 25 C and should not be used past the expiration date marked on the packaging. The injection solution requires special handling: the ampoule must be kept in its outer carton for protection from light, and the solution should be visually inspected and not used if discolored or containing particles.

Handling/Safety Mandate Requirement
Child Safety Keep this medicine out of the sight and reach of children.
Injection Use The solution is for single use only; discard any remainder immediately.

Disposal Instructions

Unused or expired Aculoid must not be thrown away via wastewater or household waste. Disposal should be done according to official local requirements, typically involving returning the medicine to a pharmacist or designated collection point.

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

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