Overview of Restavit

Property	Description
Active Ingredient	Doxylamine Succinate
Form	Oral Tablets
Pharmacological Class	First-generation Histamine H1 Receptor Antagonist
Common Use	Inducing sleep and managing occasional insomnia
Origin	Synthetic compound

What is Restavit and its Chemical Identity?

Restavit is a specific brand name for a medication whose sole active ingredient is Doxylamine Succinate, a synthetic compound. The chemical identity of Doxylamine Succinate classifies it as a First-generation Histamine H1 Receptor Antagonist. This designation indicates that the substance works by competitively inhibiting the binding of histamine at the H1 receptors located in the body and the brain. Doxylamine's molecular structure allows it to easily cross the blood-brain barrier, a key feature for its direct influence on the central nervous system.

Doxylamine Succinate: Composition and Physical Form

Doxylamine Succinate is classified as a sedating H1 antagonist. The core component responsible for the drug’s action is the Doxylamine base, which is paired with the Succinate salt form to create Doxylamine Succinate, enhancing its stability for formulation and optimizing absorption after ingestion. As a single active ingredient product, Restavit is typically manufactured as an oral tablet, a fixed-dose form used for short-term management of occasional sleeping difficulties in adults. The medication is designed solely for oral administration, allowing the active component to be absorbed via the gastrointestinal tract.

What is the General Purpose of This Antihistamine?

The general purpose of this specific antihistamine is to manage occasional difficulty falling asleep by leveraging its pronounced Central Sedative Effect, which is a direct outcome of its core mechanism. The Histamine H1 Receptor Blockade in the central nervous system dampens wakefulness signals, promoting drowsiness. Although Doxylamine is technically an antihistamine, its clinical utility in this context is centered on its strong capacity to induce CNS Depression, providing a calming influence on the nervous system to facilitate the onset of sleep.

Regulatory References

Therapeutic Uses of Restavit

Restavit (Doxylamine) is commonly used to provide short-term symptomatic support across two primary therapeutic domains. This application is relevant in clinical settings marked by temporary physiological imbalance or situational distress.

Relief of Transient Sleeplessness (Insomnia)

The medication is applied in addressing symptoms associated with transient sleeplessness and difficulty falling asleep or staying asleep. Restavit is considered relevant for managing the common and disruptive symptoms that interfere with rest, often due to temporary stress or travel. This supportive use may assist with easing the impact of the acute sleeplessness episode, contributing to a more manageable experience and supports general well-being during symptomatic phases.

Support for Mild Allergic and Cold Symptoms

Restavit helps address symptoms related to inflammatory or irritative states, such as sneezing, a runny nose, and watery eyes. This provides supportive relief that helps ease the overall discomfort. This assists with maintaining functional stability when symptoms interfere with routine activities.

Quick Fact: Relief for Difficulty Falling Asleep Restavit is commonly used to help manage the symptoms of restlessness and tension that interfere with the ability to initiate sleep.

Regulatory References

NIH MedlinePlus Drug Information

Eligibility and Restrictions for Use

Restavit (Doxylamine Succinate) is officially intended for use by adults for the short-term management of occasional sleeplessness. Eligibility is strictly defined by regulatory documents, which establish specific criteria for who must not use the medicine.

Non-Eligible and Restricted Populations

Category	Eligibility Status
Absolute Contraindications	Contraindicated in patients with hypersensitivity to the drug or other similar antihistamines, and those currently taking Monoamine Oxidase Inhibitors (MAOIs). Use is also prohibited in patients with conditions aggravated by anticholinergic effects, such as narrow-angle glaucoma or pyloroduodenal obstruction and conditions predisposing to urinary retention.
Age and Development	Contraindicated or Not Recommended in children and adolescents under 12 or 18 years of age (depending on regulatory region). Caution is required for use in the elderly due to increased susceptibility to effects.
Organ Function/Status	Use requires caution in patients with hepatic (liver) or severe renal (kidney) impairment. The medicine is not recommended for use during pregnancy or while breastfeeding.

Official eligibility documentation establishes that use is strictly limited to the adult population without these specific contraindicating conditions or physiological states.

What should I know about interactions with other medicines?

The official regulatory classification for Doxylamine Succinate identifies several categories of pharmacodynamic interactions and a formal contraindication.

Contraindicated Combinations and Restrictions

The most stringent regulatory restriction is the contraindication of co-administration with Monoamine Oxidase Inhibitors (MAOIs), or agents possessing MAOI activity (e.g., linezolid or procarbazine). This restriction is due to the potential to prolong and intensify the anticholinergic and Central Nervous System (CNS) depressant effects of doxylamine. This classification establishes a mandatory 14-day separation period between discontinuing MAOI therapy and beginning treatment with doxylamine.

Pharmacodynamic Synergism and Additive Effects

The concurrent use of Doxylamine Succinate with alcohol (ethanol) or other CNS depressants (including hypnotic sedatives, narcotic analgesics, and anxiolytics) is officially not recommended. This combination is documented to result in an additive depressant effect, leading to severe drowsiness.

Other documented interactions include the potentiation of adverse effects when combined with agents that have anticholinergic properties. Furthermore, caution is advised with drugs known to prolong the QT interval or those that cause electrolyte disturbances, which may increase the risk of cardiac rhythm changes.

Precautionary avoidance of potent CYP enzyme inhibitors is also noted in regulatory documents, based on the known metabolism of Doxylamine. Caution is also noted for use in patients with hepatic or renal impairment, as reduced clearance may modify the overall interaction profile.

The regulatory documents establish the product's interaction structure primarily around pharmacodynamic synergism that mandates the prohibition of use with MAOIs and the avoidance of other CNS depressants.

Mechanism of Action

Restavit's mechanism of action is defined by its interaction with key neurotransmitter systems in the central nervous system ( CNS). Its function is to modulate signaling in the histaminergic pathway, which is associated with wakefulness.

Modulating Arousal Signals via Central Histamine H1 Blockade

The primary mechanism involves the competitive antagonism of Histamine H1 Receptors within the brain. The molecule's high lipophilicity allows it to easily penetrate the blood-brain barrier, where it suppresses the histaminergic pathway—a major component of the Ascending Reticular Activating System (ARAS). Interrupting this core wakefulness cascade causes a reduction in overall neuronal excitability and leads to a physiological state of Central Nervous System ( CNS) depression.

Secondary Influence on Cholinergic Signaling Pathways

In addition to its primary target, the drug engages a secondary mechanistic domain through antagonism of Muscarinic Acetylcholine Receptors ( M-AChR). This non-selective action modulates cholinergic signaling, influencing pathways related to arousal and various involuntary autonomic functions. This dual action results in a physiological effect profile that includes consequences beyond the singular H1 blockade.

Dosage and Administration Information

How to Use Restavit: Official Administration Guidelines

Restavit (Doxylamine Succinate) is a single-ingredient product administered exclusively via the oral route for short-term use. The official instructions define the dosage, timing, and population-specific rules for standardized administration.

Administration Parameter	Official Labeled Instruction
Standard Adult Dose	25 mg for adults and adolescents aged 12 years and over.
Frequency and Timing	Once daily, taken approximately 20 to 30 minutes prior to the intended time of sleep onset.
Administration Condition	Should be swallowed with a glass of water. May be administered without regard to meals.
Duration of Use	Intended strictly for short-term or occasional use.

Population-Specific and Procedural Instructions

The medication is not intended for use in pediatric patients younger than 12 years of age. For older adults or individuals with impaired hepatic (liver) or renal (kidney) function, a dosage reduction—often to 12.5 mg—may be warranted to mitigate sensitivity. This lower dose is facilitated by a break bar on the 25 mg tablet, allowing for accurate dose halving. The overall administration protocol establishes a clear, time-bound regimen that must not exceed the once-daily frequency.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Restavit (Doxylamine)

Evidence for Use in Short-Term Sleeplessness

Research examining Doxylamine for temporary difficulty falling asleep includes Randomized Controlled Trials (RCTs) and larger scale systematic reviews. These studies are applied in research exploring how sleep patterns change over short periods, typically comparing the medication to a placebo (a dummy pill). Studies explored outcomes related to patient-reported outcomes describing perceived discomfort and monitoring the functional imbalance of sleeplessness. These factors included the time patients took to fall asleep (sleep latency) and the recorded length of time they remained asleep (total sleep time).

Studies monitored patterns related to sleep onset, where the time measured to fall asleep was observed to be shorter in the groups receiving the medication compared with the control groups. Research describes patterns where total sleep duration was observed to be longer in the groups receiving the medication. However, the evidence is relevant in trials assessing short-term or episodic symptom patterns, meaning the findings describe patterns observed only over limited time intervals, such as a single night or up to four weeks.

Evidence for Mild Allergy and Cold Symptom Research

Doxylamine was studied for its application in conditions characterized by fluctuating or episodic manifestations, such as those associated with mild allergies or the common cold. The research base here relates to the drug’s classification as a First-Generation H1 Antihistamine. Studies examined specific outcomes linked to inflammatory or irritative states, such as monitoring the frequency of sneezing and subjective reports of a runny nose (rhinorrhea).

Findings describe patterns observed in the studies where the medication was associated with changes measured in outcomes related to physical discomfort. Research describes patterns where studies reported specific changes in symptom intensity during the monitored periods. However, findings were mixed when the research attempted to evaluate the overall symptom intensity for the common cold.

Long-Term Data and Durability of Effect

The research exploring short-term symptom changes provides limited information for long-term outcomes related to Doxylamine use. The vast majority of the evidence is derived from settings with varying symptom burdens over defined time intervals that rarely exceed four weeks. Research indicates that the body may develop tolerance to the medication's effects, meaning the observed patterns may lessen after just a few days of repeated use. As a result, the long-term effects are not fully established, and evidence for chronic or ongoing sleep disorders is considered insufficient.

Key Studies & References

Frequently Asked Questions (FAQ)

Common questions about Restavit (FAQ)

Q: Is it safe to take Restavit with common pain relievers like paracetamol or ibuprofen?

Official information on drug interactions does not specifically cite a direct drug-to-drug interaction between doxylamine (the active ingredient in Restavit) and common pain relievers like paracetamol (acetaminophen) or ibuprofen. However, regulatory warnings describe the need for caution when combining medications.

For any medication combination, the product information outlines the importance of following the recommended maximum daily dose for each product to avoid accidental overdose.

Q: What is the recommended maximum duration of use?

Regulatory documents emphasize that Restavit is intended for short-term or occasional use only in managing temporary sleeplessness. Official labeling may indicate that consulting a healthcare provider is suggested if sleeplessness continues for longer than a few days or one to two weeks, depending on the region's specific guidance. This guidance is provided as the medication is intended only for temporary, occasional sleeplessness.

Q: Is there any risk of developing tolerance or dependence on Restavit?

Official product information notes that using the medication for long periods is generally not recommended due to the possibility of developing tolerance, meaning the effect may lessen over time with repeated use. Although the active ingredient is not classified as a controlled substance, the official recommendation to limit use to the short-term is intended to mitigate the risk of reliance on the medication for sleep.

Q: Are there known interactions between Restavit and herbal supplements like valerian or kava?

The active ingredient in Restavit works by causing central nervous system (CNS) depression, which means it slows down activity in the brain. Regulatory warnings indicate that the medicine may potentiate the effects of other substances that also cause central nervous system (CNS) depression, including some herbal supplements. For this reason, official sources describe that concurrent use with any other sedatives or CNS depressants should be avoided.

How should Restavit be stored and disposed of?

How to Store and Dispose of Restavit?

The storage and disposal of Restavit (Doxylamine Succinate) tablets must strictly follow the official instructions provided on the regulatory label to maintain product stability and ensure safety.

Storage Requirements

Temperature and Environment: The medicine must be stored below 30 C in a dry place. Users must not store the tablets in environments prone to heat and moisture, such as bathrooms, or expose the product to freezing temperatures.
Packaging and Stability: Tablets must be kept in the original container with the lid tightly closed and must not be used past the printed expiry date.
Child Safety: It is a mandatory requirement to keep the product out of the sight and reach of children.

️ Disposal Instructions

To dispose of unused or expired Restavit, follow official pharmaceutical waste guidelines. Do not discard the medicine in domestic garbage bins or flush it down the toilet. The recommended procedure is to return the unwanted tablets to a local community pharmacy for proper and safe disposal.

System-Organ Class	Common Adverse Reactions
Nervous System	Drowsiness, Dizziness, Headache
Gastrointestinal	Dry mouth, Constipation
Eye Disorders	Blurred vision

System	Symptoms
Central Nervous System (CNS)	Impaired consciousness, delirium, seizures, coma
Cardiovascular	Tachycardia, cardiorespiratory arrest, cardiovascular collapse
Other Systems	Respiratory failure, rhabdomyolysis (muscle breakdown) with acute kidney impairment

Restavit