Sominal

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Sominal

Medically reviewed

Laura Arias

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 Sominal

Quick Facts

Property Description
Active Ingredient Phenobarbital (Phenobarbitone)
Form Tablets, Oral Solution (Elixir), Injectable Solution
Pharmacological Class Barbiturate, Central Nervous System (CNS) Depressant
Common Use Stabilizing nerve activity
Origin Synthetic (Barbituric Acid Derivative)

Defining the Pharmaceutical Entity and Drug Class

Sominal is a medication containing the single active ingredient Phenobarbital, which is also known as Phenobarbitone. This substance is categorized as a potent Central Nervous System (CNS) depressant and is chemically classified as a barbiturate.

Phenobarbital is a synthetic compound derived from barbituric acid, with the molecular formula C12H12N2O3. The medication is prepared in multiple dosage forms, including oral tablets, liquid solutions, and injectable solutions, providing therapeutic flexibility for various routes of administration, such as oral, intravenous, and intramuscular.

Mechanism, General Therapeutic Purpose, and Context

The general therapeutic purpose of Sominal is to provide a stabilizing effect on brain function. It works by reducing the overall electrical excitability of the central nervous system, thereby raising the level of stimulation needed to trigger aberrant nerve firing. By decreasing neural activity, Sominal provides a strong sedative effect which is typically leveraged when medical intervention requires calming severe restlessness or achieving profound CNS depression.

Unlike newer, short-acting agents, Phenobarbital is known for its long duration of action and remains one of the longest-established medications for specialized sedation and nerve stabilization. Phenobarbital is included on the World Health Organization (WHO) Model List of Essential Medicines, confirming its significance in global health systems. Sominal is classified as a prescription-only medication, necessitating professional oversight for its appropriate therapeutic application.

Regulatory References

  1. Phenobarbital on WHO Electronic Essential Medicines List

What side effects are possible with Sominal?

Official Safety Profile and Adverse Reactions

The safety profile of Sominal, which contains phenobarbital, is documented according to regulatory standards, classifying possible adverse reactions by frequency and the body system affected. As a central nervous system (CNS) depressant, many reported effects involve the neurological system.

Adverse reactions classified as More Common (estimated incidence of 1 to 3 patients per 100 in FDA data) include somnolence (drowsiness/sleepiness) [NIH DailyMed]. Reactions reported as Less Common (incidence less than 1 in 100) encompass CNS effects such as confusion, agitation, nervousness, and ataxia (lack of coordination), alongside gastrointestinal effects like nausea, vomiting, and constipation [NIH DailyMed].

Serious Adverse Reactions and Safety Constraints

The regulatory profile explicitly names serious, potentially life-threatening reactions. These include severe respiratory depression, circulatory collapse, and serious dermatological events, specifically Stevens-Johnson syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) [HPRA SmPC]. The highest risk for these severe cutaneous reactions is generally reported to be within the initial weeks of treatment [HPRA SmPC].

Safety notes for specific populations are detailed in official labels. Older adults and pediatric patients may experience paradoxical reactions, including excitement, restlessness, or confusion [NIH DailyMed]. The medication is subject to high-level constraints, including being contraindicated in patients with a history of hypersensitivity to barbiturates or pre-existing severe hepatic impairment [HPRA SmPC]. Prolonged use is associated with the risk of physical dependence, and controlled cessation is necessary to avoid potentially life-threatening withdrawal reactions [NIH DailyMed].

Overdose and Emergency Response

Overdose and When to Seek Help

This section outlines the officially documented clinical presentations and required emergency actions for Sominal overdose, based strictly on government regulatory labeling (e.g., FDA, EMA).

Documented Manifestations and Risks

Overdosage of Sominal is associated with a progression of Central Nervous System (CNS) depression ranging from severe somnolence to stupor and unresponsiveness. The most serious life-threatening outcomes documented in regulatory sources are respiratory depression (slowed or shallow breathing) and significant cardiovascular compromise, including profound hypotension. The risk of severe toxicity is noted to increase proportionally with the dose ingested.

Specific populations, such as elderly patients, may experience a more severe or prolonged overdose course, a factor noted in official labeling due to altered drug metabolism.

Emergency Actions and Management

Immediate medical attention is required for any suspected Sominal overdose. Regulatory documents explicitly state that contact with emergency medical services or a certified poison control center must occur immediately upon recognition of ingestion of an excessive dose or observation of any symptoms.

Urgent medical help must be sought if the individual exhibits any sign of respiratory compromise, inability to be roused, or sustained low blood pressure. Management, as defined by regulatory standards, focuses on providing supportive care to maintain vital functions, ensure a patent airway, and monitor cardiac activity. If documented in official labeling, a specific pharmacological antidote may be administered in a clinical setting by healthcare professionals.

Therapeutic Uses of Sominal

What Sominal Treats: Main Uses and Benefits

The core therapeutic domain of this medication may be part of symptomatic management for symptoms related to heightened physiological activity that are linked to the inability to fall asleep, which may include difficulty falling asleep and temporary sleeplessness. This medication is considered relevant for easing symptoms that interfere with daily functioning due to these conditions.

This medication is commonly used to help manage symptoms that interfere with daily functioning which are generally associated with acute or episodic changes in sleep patterns. It is commonly used to help ease symptoms related to heightened physiological activity that can prevent rest, which is often used during phases when symptoms become more noticeable. Sominal supports patients during episodes of heightened discomfort and may help patients cope more steadily with symptom fluctuations. This is applied in addressing the symptom cluster when short-term symptomatic assistance is needed.

“This supportive relief contributes to easing the overall symptom load during symptomatic periods.”

Quick Fact: Relief for Temporary Sleeplessness

Regulatory References

  1. NIH DailyMed label for Sominex

Eligibility and Restrictions for Use

Official Eligibility Profile for Sominal

This information reflects only the documented population eligibility and restrictions as stated in official regulatory labeling.

Eligibility Scope

Population Status Regulatory Guidance (Label-Based)
Use is Contraindicated Patients with known hypersensitivity to Sominal or its inactive ingredients. Any patient with a history of a complex sleep behavior (e.g., sleepwalking) following use of this or similar agents. Patients with severe hepatic impairment (uncontrolled liver disease).
Use is Restricted Patients with moderate to severe renal or hepatic impairment require mandatory dosage adjustments and close monitoring; use is limited and generally avoided in severe cases. Older adults (65 years and over) require a lower maximum dose.
Use Not Established Pediatric patients (under 18 years of age) due to insufficient data on efficacy and safety, meaning use is not officially recommended.
Pregnancy/Lactation Pregnancy: Use is generally not recommended unless the potential benefit outweighs the documented potential risk to the fetus. Lactation: Not recommended; the drug is excreted in breast milk.

These constraints establish the formal boundaries of the population for whom Sominal has been authorized. The regulatory documents define eligibility by strictly prohibiting use in contraindicated groups and imposing specific restrictions on patient groups with impaired organ function or developmental vulnerabilities.

What should I know about interactions with other medicines?

The medication Sominal has been historically associated with agents that possess central nervous system (CNS) depressant properties, such as diphenhydramine. Consequently, its primary interaction profile involves a heightened risk of sedation and other CNS-related effects when taken alongside specific categories of medicinal products.

Documented Interaction Categories

Category Interaction Mechanism Clinical Relevance
CNS Depressants Additive CNS depression Increased drowsiness, dizziness, respiratory risk
Alcohol (Ethanol) Additive CNS depression Increased impairment and sedative effects
Anticholinergics Enhanced anticholinergic burden Increased risk of dry mouth, confusion, urinary retention

Key Interacting Medicines

Interactions are specifically noted with other medicines that cause sedation, including opioid pain relievers, drugs for anxiety or sleep (e.g., benzodiazepines, zolpidem), tricyclic antidepressants, and muscle relaxants. The combination of these agents can significantly amplify the potential for drowsiness and impaired coordination, leading to substantial clinical risk.

Procedural and Safety Notes

Individuals should strictly avoid consuming alcohol while using Sominal due to the significant potentiation of CNS depression. It is essential to inform a healthcare provider of all current medications, including over-the-counter products and herbal supplements, before starting treatment. This comprehensive review is necessary to manage additive effects and mitigate the risk of serious side effects arising from pharmacokinetic or pharmacodynamic interactions.

Mechanism of Action

Sominal is a pharmaceutical agent that acts on the central nervous system by modulating the activity of the gamma-aminobutyric acid type A ( GABA A) receptor complex. Specifically, Sominal functions as a positive allosteric modulator of the GABA A receptor, binding at a site distinct from the endogenous neurotransmitter GABA. This non-competitive binding facilitates the intrinsic effect of GABA, promoting an increased frequency of chloride ion channel opening.

The resulting enhanced chloride ion influx hyperpolarizes the postsynaptic neuronal membrane, increasing the transmembrane potential difference. This hyperpolarization diminishes the excitability of neurons across various central nervous system structures, including the thalamus and cortex. The downstream cascade is a general depression of neuronal activity, which results in a system-level physiological consequence of decreased central nervous system arousal and global electroencephalographic slowing, consistent with a reduced state of wakefulness.

Dosage and Administration Information

How to Use Sominal

Sominal, which contains Phenobarbital, is administered through multiple routes depending on the clinical context. For routine, long-term use and maintenance, the drug is primarily administered orally in the form of tablets or an elixir. For acute, time-sensitive needs, it is administered as an injectable solution, typically via the intramuscular (IM) or slow intravenous (IV) routes.


Standard Dosing and Frequency

Dosing regimens are categorized based on the usage pattern:

  • Sedation: Total daily doses generally range from 30 mg to 120 mg, usually administered in two or three divided doses throughout the day.
  • Hypnotic Use (Insomnia): Doses for short-term sleep assistance range from 100 mg to 320 mg and are taken as a single dose immediately before bedtime.
  • Anticonvulsant Maintenance: Standard doses fall between 60 mg and 200 mg daily, often taken once daily due to the drug's long half-life.

Administration Requirements and Duration

Sominal tablets and oral solutions may be taken without regard to food. If administering the injectable solution, the intravenous infusion rate in adults must not exceed 60 mg/minute to ensure proper use.

For specific populations, lower doses are indicated for older adults and individuals with impaired hepatic or renal function. Usage for insomnia is designated as short-term, generally not to exceed 14 days. Following prolonged use, discontinuation must be performed gradually.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Sominal

Evidence for Use in Chronic Insomnia

Research examining Sominal for conditions characterized by functional limitations related to sleep, specifically chronic insomnia, has primarily involved short-term and intermediate-term Randomized Controlled Trials (RCTs). These studies was studied for exploring short-term symptom changes in adult patients presenting with cycles of stability and flare-ups in sleep patterns. Researchers monitored objective outcomes in areas like physiological metrics using Polysomnography (PSG), which included measuring metrics like Total Sleep Time and the time it took for a person to fall asleep.

Studies exploring short-term symptom changes have reported measurements showing a pattern of change in objective sleep metrics compared to inactive treatment (placebo). Findings describe patterns observed in the studies, where patients recorded shifts in measured sleep outcomes during the defined time interval. Furthermore, research describes changes measured during the study period related to patient-reported outcomes describing perceived discomfort with sleep quality.

Comparing Sominal to Placebo and Other Treatments

The clinical program for Sominal has explored trials that compared its measured outcomes to an inactive pill (placebo) and also trials that was studied for comparison against other approved medications. Studies report how symptoms evolved in the observed populations, but variability across studies was observed depending on the specific active comparator used and the measured outcome. Research exploring short-term symptom changes contributes to understanding short-term changes, but direct comparative certainty remains low for certain axes of outcome.

What Is Still Uncertain About Sominal

While numerous short-term RCTs was studied for Sominal, several research limitation frames apply. Data for certain groups remain insufficient, particularly for those with severe concurrent medical conditions. Long-term effects are not fully established; evidence for populations such as pregnant individuals, children, and adolescents is limited and data are still emerging, meaning results apply only to the populations studied. The findings describe group patterns observed under the specific conditions of the trials, and research cannot predict whether an individual will respond similarly.

Frequently Asked Questions (FAQ)

Common questions about Sominal (FAQ)


Q: How quickly should I expect to feel the effects of Sominal?

A: According to official product information, when Sominal is taken orally, its absorption into the body is slow. Peak concentrations in the blood typically take several hours to reach after the dose is administered. The full effects may take some time to be noticed due to its slow absorption.


Q: How long does the feeling or effect of Sominal usually last?

A: Sominal is classified as a long-acting barbiturate, and its clinical effect can last for approximately 6 to 12 hours. However, the body takes a very long time to eliminate it, with an average half-life in adults of around 79 hours. This long half-life contributes to its use in long-term treatment regimens.


Q: Is it normal to feel a bit groggy or 'hungover' the day after taking Sominal?

A: Official regulatory labels indicate that residual sedation, sometimes described as a 'hangover' effect, may occur. This is a possibility because the medicine acts as a central nervous system depressant. Concerns about residual effects should be brought to the attention of a health professional.


Q: Is Sominal safe for older adults or the elderly?

A: Official guidelines state that older adults may require a lower dose of Sominal and require close monitoring to address potential effects. There is also a specific warning that older adults may experience paradoxical reactions, such as confusion, restlessness, or excitement, which are opposite to the intended sedative effect.


Q: Does Sominal show up on drug tests?

A: Sominal's active ingredient, phenobarbital, belongs to the barbiturate class of medicines. Barbiturates are included in certain drug screening panels.


Q: Can you build up a tolerance to Sominal over time?

A: Yes, official regulatory warnings state that tolerance may occur, especially following the prolonged use of high doses. Developing tolerance means that a person may require a larger amount of the drug to achieve the same initial effect.


Q: Does Sominal affect your memory or concentration?

A: Regulatory documents indicate that side effects can include confusion and agitation. The medication is also known to have the potential to impair the mental and physical abilities required for the performance of hazardous tasks.


Q: Can men and women expect different side effects from Sominal?

A: General regulatory documents do not specify different side effect profiles for men and women. However, there are specific warnings and advice for women of childbearing potential, including risks during pregnancy and potential interactions with hormonal contraceptives.


Q: What types of drug interactions are the most concerning with Sominal?

A: The most concerning interactions involve taking Sominal alongside other central nervous system (CNS) depressants, such as opioids and alcohol. This combination carries a significant risk of profound sedation, severe respiratory depression, and potentially life-threatening complications.


Q: Is there a generic version of Sominal available?

A: Yes, the active ingredient in Sominal, which is phenobarbital, is widely available as a generic medication. It comes in various dosage forms, including tablets and oral solutions.


Q: What should I do if a side effect from Sominal doesn't go away?

A: Regulatory documents state that users should seek immediate professional medical attention for serious adverse reactions. Concerns about persistent or non-resolving side effects, even common ones, should be raised with a healthcare professional.


Q: How should Sominal be stored (temperature, light, etc.)?

A: Official guidelines recommend storing Sominal tablets at a controlled room temperature, typically between 68 F and 77 F (20 C and 25 C). It must be kept in its container, tightly closed and protected from moisture and light, to ensure its stability.


Q: Is it common for people to take Sominal only when they need it, or every day?

A: Usage varies based on the purpose of the treatment. When used for sleep (hypnotic use), it is generally taken as a single dose before bedtime and is intended for short-term use. For conditions like seizure management, it is typically prescribed to be taken daily.


Q: Can you develop an allergy to Sominal after using it for a while?

A: Yes, acquired hypersensitivity reactions can occur, even after initial use. Regulatory documents report allergic reactions, such as skin rashes, which have been noted in individuals using phenobarbital.


Q: Has the FDA (or similar agency) approved Sominal for its intended purpose?

A: The active ingredient in Sominal, phenobarbital, has received regulatory approval for its various intended uses, such as seizure management and sedation. This long-established medicine is also included on the World Health Organization's Model List of Essential Medicines.


Q: What age group is Sominal generally not recommended for?

A: Official information generally does not recommend Sominal for children and adolescents. This restriction is primarily due to insufficient data to establish both the efficacy and safety of the medicine in these specific age groups.


Q: Should I tell my dentist I'm taking Sominal before a procedure?

A: Official patient counseling materials recommend that all healthcare providers, including dentists, be made aware of all medications being taken. This is important because Sominal can interact with other central nervous system depressants often administered during dental procedures.


Q: Can Sominal affect my ability to drive or operate machinery?

A: The regulatory label explicitly warns that the medication may impair the mental and physical abilities required for performing potentially hazardous tasks. The impairment risk requires caution when engaging in activities such as driving or operating heavy equipment.


Q: Does the body break down Sominal quickly or slowly?

A: The active ingredient in Sominal is known to be metabolized slowly by the liver, which is a major factor contributing to its long half-life. A portion of the drug is also excreted by the kidneys.


Q: Why is Sominal sometimes prescribed over other similar drugs?

A: Sominal's active ingredient is noted for its long duration of action compared to many other agents. Its status on the World Health Organization's Model List of Essential Medicines also confirms its long-established and important role in various health systems globally.


Q: Does the effectiveness of Sominal decrease the longer you take it?

A: Official warnings mention that tolerance to the drug's effects can develop with continued use. This means that over time, the initial therapeutic dosage may become less effective.


Q: Is it true that Sominal can cause changes in behavior or mood?

A: Yes, regulatory documents report that Sominal can cause changes in behavior or mood. These effects may include excitement, confusion, irritability, nervousness, or even more serious mental health changes like hallucinations or suicidal ideation.


Q: Is Sominal available in different strengths?

A: Yes, official product information confirms that the active ingredient in Sominal is available in multiple tablet strengths, as well as an oral liquid solution. This variety allows for flexibility in therapeutic management.

How should Sominal be stored and disposed of?

Official Storage and Handling Requirements

The regulatory label for Sominal mandates storage at controlled room temperature (e.g., typically below 25 C or 30 C), and explicitly states to not freeze the product. To protect the medicine's stability, it must be kept in its original outer carton to shield it from light and moisture.

Specific stability constraints apply if the product is reconstituted: the solution must be used within a defined period (e.g., 14 days) and then discarded. All medicines, including Sominal, must be stored out of the sight and reach of children.

Disposal Instructions

To dispose of unused or expired Sominal, follow official guidance by using a medicine take-back program or an authorized collector whenever available. Do not dispose of this medication by flushing it down the toilet or pouring it down a drain, as this prevents environmental contamination. If no take-back program is accessible, follow patient leaflet instructions for safe household disposal, typically by mixing the drug with an undesirable substance.

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

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