Overview of Donnatal

Property	Description
Active Ingredients	Phenobarbital, Hyoscyamine Sulfate, Atropine Sulfate, Scopolamine Hydrobromide
Form	Oral Tablet (immediate and extended-release), Oral Elixir
Pharmacological Class	Anticholinergic Agent (Antispasmodic) and Barbiturate Sedative
General Purpose	Relief of symptoms associated with gastrointestinal functional distress
Origin	Semi-synthetic (Barbiturate plus natural alkaloid derivatives)

What Type of Medicine is Donnatal?

Donnatal is a fixed-dose combination product (FDC), distinguished by its dual pharmacological classification as an Anticholinergic Agent (Antispasmodic) and a Barbiturate Sedative. This prescription preparation is intended for oral use, designed to deliver both muscle relaxation and mild sedation in a single unit. It is available in distinct forms, including the standard Oral Tablet, an extended-release tablet (Donnatal Extentabs), and a liquid Oral Elixir, which is often suitable for patients who have difficulty swallowing solids.

What is the Composition of Donnatal?

The combination is characterized by a precise, fixed ratio of its four active ingredients: the mild sedative Phenobarbital, and the three Belladonna Alkaloids—Hyoscyamine Sulfate, Atropine Sulfate, and Scopolamine Hydrobromide. This medicine has a semi-synthetic origin, blending the synthetic Phenobarbital compound with anticholinergic derivatives of natural alkaloids. This fixed composition, which is less common in contemporary GI treatments, provides a differentiated option compared to single-ingredient antispasmodics.

General Purpose and Core Effect

The primary purpose of Donnatal is to offer relief from symptoms of distress within various Gastrointestinal Conditions that benefit from both muscle control and nervous system calming. The drug combination provides peripheral anticholinergic/antispasmodic action and mild sedation. This means the preparation helps ease discomfort by simultaneously reducing involuntary muscle spasms in the gut and lowering the associated nervous tension, addressing the multifaceted nature of conditions like Irritable Bowel Syndrome (IBS).

Regulatory References

What side effects are possible with Donnatal?

Possible side effects and safety information

The regulatory documentation for Donnatal (phenobarbital, hyoscyamine sulfate, atropine sulfate, scopolamine hydrobromide) notes that adverse reactions reflect the combined pharmacological action of its anticholinergic and barbiturate components. Official labeling generally groups these effects by the physiological system affected.

Adverse reactions associated with the Gastrointestinal System include xerostomia (dry mouth), constipation, nausea, vomiting, and a bloated feeling. Effects noted in the Nervous System include drowsiness, dizziness, headache, nervousness, and weakness. Ocular effects are defined as blurred vision, mydriasis (pupil dilation), and increased ocular tension. Other documented reactions include tachycardia, palpitation, urinary hesitancy and retention, and decreased sweating.

Serious Safety Considerations and Special Risk Patterns

Serious adverse reactions documented in the labeling include severe hypersensitivity and rare, potentially fatal, skin reactions such as Exfoliative dermatitis (including Stevens-Johnson syndrome). The Phenobarbital component carries the risk of physical and psychological dependence with repeated administration; abrupt withdrawal in habituated patients may result in severe complications, including delirium or convulsions.

Special safety notes exist for Elderly patients, who may experience heightened effects like excitement, agitation, and drowsiness even at small doses. Safety information also emphasizes that in the presence of a high environmental temperature, heat prostration (fever and heatstroke) can occur due to the decreased sweating caused by the belladonna alkaloids. Furthermore, the label notes that diarrhea may signal an incomplete intestinal obstruction, in which case the medicine's use is inappropriate.

Overdose and Emergency Response

Overdose and When to Seek Help

An overdose of Donnatal is associated with toxicological effects from both its anticholinergic components and the barbiturate sedative, phenobarbital. The potential manifestations include headache, nausea, vomiting, dizziness, blurred vision, and dilated pupils (mydriasis). Other signs may involve hot and dry skin, difficulty in swallowing, and central nervous system effects ranging from stimulation to profound depression.

The ingestion of excessive amounts carries a significant risk of severe, life-threatening outcomes. These documented serious consequences include fatal respiratory arrest and circulatory collapse, particularly due to the barbiturate element.

Emergency Actions

Immediate medical attention is required for any suspected overdose. It is imperative to contact a Poison Control Center or doctor immediately.

Management: Treatment is primarily symptomatic and supportive. Regulatory documents describe specific procedures that may be used, such as gastric lavage, the administration of emetics, or activated charcoal.
Specific Intervention: For the anticholinergic component, the use of parenteral cholinergic agents (such as physostigmine) is a documented option if medically indicated to reverse specific effects.
Population Note: Elderly patients are noted to exhibit increased sensitivity, potentially reacting to smaller exposures with heightened excitement, agitation, and drowsiness.

Therapeutic Uses of Donnatal

Donnatal's Main Therapeutic Focus: Symptom Management

Donnatal is a prescription medication commonly used to help manage symptoms related to physical discomfort in the gastrointestinal tract. This medicine is often utilized to help relieve cramping pains in conditions like irritable bowel syndrome (IBS) and spastic colon, and is applied to offer supportive, short-term relief.

Easing Symptomatic Discomfort in Digestive and Abdominal Issues

This therapeutic domain is relevant for easing symptoms related to heightened physiological activity in the gut. The medication may assist with maintaining functional stability and supports the patient by helping to ease the overall burden of abdominal discomfort and noticeable physiological strain. The conditions in which this medication may be used as part of supportive care include Irritable Bowel Syndrome (IBS), irritable colon, spastic colon, mucous colitis, and acute enterocolitis.

Support for Conditions with Episodic or Fluctuating Symptoms

The medicine is applied in clinical settings that involve acute or unstable symptom patterns, such as conditions characterized by periods of heightened symptoms or episodic manifestations. It contributes to improved comfort during symptomatic periods and may assist with maintaining functional stability when symptoms interfere with routine activities.

Quick Fact: Relief for Abdominal Cramping

Regulatory References

NIH MedlinePlus overview

Eligibility and Restrictions for Use

Eligibility Map: Who can and cannot use Donnatal

Official regulatory documents strictly define the patient population eligible to use Donnatal (Phenobarbital, Hyoscyamine Sulfate, Atropine Sulfate, Scopolamine Hydrobromide).

Populations for whom use is allowed (as stated in label):

Adults requiring adjunctive therapy for specified functional gastrointestinal disorders.

Populations for whom use is contraindicated:

Patients with glaucoma, obstructive diseases of the gastrointestinal or urinary tract, or myasthenia gravis.
Individuals with a history of drug dependence or known hypersensitivity to any component or to barbiturates.
Patients with severe hepatic or renal disease or acute intermittent porphyria.

Age and Physiological Restrictions:

Pediatric Patients: Safety and effectiveness have not been established.
Older Adults (Geriatric Use): Requires caution due to increased sensitivity and potential for adverse reactions.
Pregnancy: The drug is assigned Pregnancy Category D or is stated to cause fetal harm (depending on formulation).
Lactation: Use is not recommended for nursing mothers, as components may be excreted in human milk.

Eligibility-Related Restrictions:

Use with caution in patients with certain cardiovascular conditions (e.g., coronary heart disease, tachycardia) and conditions like autonomic neuropathy.

What should I know about interactions with other medicines?

Interactions with Other Medicines and Products – Official Regulatory Information

This section outlines interaction patterns documented in official regulatory sources for Donnatal.

Category	Interacting Agents and Official Description
Metabolic Interactions	Phenobarbital induces hepatic microsomal enzymes, which leads to increased metabolism and consequently decreases the effect of co-administered drugs. Affected agents include Anticoagulants (Warfarin, Dicumarol), Hormonal Contraceptives, Corticosteroids, and Doxycycline. Furthermore, Monoamine Oxidase Inhibitors (MAOIs) interact by inhibiting the metabolism of Phenobarbital, thereby prolonging its effects.
Pharmacodynamic Effects	Co-administration with CNS Depressants (including Alcohol) is documented to produce additive depressant effects (e.g., drowsiness and impaired reactions). Use with solid-dosage Potassium Supplements may increase the risk of gastrointestinal irritation due to delayed gastric emptying caused by the anticholinergic components.
Timing Requirements	Antacids and Antidiarrheal Agents may reduce the absorption of the belladonna alkaloids. Official documents require at least 3 hours separation between the administration of Donnatal and these products to ensure proper absorption.
Population Notes	Patients with Hepatic Dysfunction may experience increased effects of the Phenobarbital component due to slower clearance, a factor based on the drug's metabolism in the liver.

The official regulatory profile is defined by the metabolic enzyme induction from Phenobarbital, which can reduce the systemic exposure of numerous co-administered drugs, and the pharmacodynamic risks of additive CNS effects. This structure also establishes specific timing constraints for administration with certain agents to maintain drug absorption as documented in official labeling.

Mechanism of Action

How Donnatal Works: Dual Mechanistic Action

Donnatal exerts its effects through the combined modulation of peripheral autonomic signaling and central nervous system excitability.

Blocking Overactive Gastrointestinal Signaling

The belladonna alkaloids ( hyoscyamine, atropine, and scopolamine) function as competitive antagonists at muscarinic acetylcholine receptors ( mAChRs) located on smooth muscle and glandular cells within the gastrointestinal ( GI) tract. By binding to these receptors, they disrupt the signal transduction cascade mediated by the neurotransmitter acetylcholine. This interference suppresses the nerve impulses that drive involuntary muscle contraction and glandular secretion. This mechanistic consequence results in the inhibition of smooth muscle contraction and glandular output, influencing the degree of GI motility and secretion of stomach acid.

Modulating Central Nervous System Excitability

The fourth component, phenobarbital, interacts with the GABA-A receptor complex in the central nervous system ( CNS). It functions as a positive allosteric modulator, enhancing the inhibitory effect of the neurotransmitter GABA (gamma-aminobutyric acid). This potentiation increases the influx of chloride ions, leading to hyperpolarization of the neuronal membrane, which decreases general neuronal excitability. This mechanistic outcome is characterized by CNS depression.

Dosage and Administration Information

The administration of Donnatal is exclusively by the oral route, with dosage structured across three distinct forms: the standard tablet, the liquid elixir, and the extended-release tablet (Extentab). The fundamental principle guiding its use is that the total dose must be strictly individualized to the patient's symptomatic needs, aiming to achieve control using the lowest possible effective amount and frequency.

Standard Adult Regimens

For the standard tablet and elixir forms, the typical adult dosing regimen involves taking one or two units (tablets or 5 mL teaspoonfuls of elixir) three or four times a day. Conversely, the extended-release Extentab tablet is formulated for gradual delivery, requiring a regimen of one tablet every twelve hours. This Extentab must be swallowed whole and should not be crushed, broken, or chewed.

Dosing Adjustments and Precision

Official guidelines specify that small initial doses are required when initiating treatment in older adults and in patients with hepatic dysfunction. For pediatric patients, the liquid Elixir is dosed based on body weight and must be measured precisely using a pediatric dosing device or oral syringe. The phenobarbital component introduces a necessary prescribing constraint: if the patient is taking oral anticoagulants, the anticoagulant dose must be increased when Donnatal is started and subsequently decreased when it is discontinued.

Recent Clinical Evidence

Research evidence / Overview of studies for Donnatal

Irritable Bowel Syndrome (IBS)

Research exploring the use of Donnatal for Irritable Bowel Syndrome has typically focused on whether it may affect common IBS symptoms, particularly pain and cramping associated with the condition. These studies have often been smaller and conducted over several decades, meaning the research may not reflect the modern, rigorous standards often used today.

Early clinical trials, which often compared Donnatal to an inactive substitute (a placebo), explored whether it could influence some of the symptoms reported in IBS. These study findings indicated that a reduction in the severity of abdominal pain and bowel spasm was reported for some people using the medication. However, findings across all studies have not been entirely consistent, and results were sometimes mixed.

A key challenge in the research is the lack of large-scale, recent studies, which means confidence in the findings is limited. Therefore, while some initial findings indicated certain symptomatic changes, the long-term effects and its role alongside current treatment approaches remain unclear. More modern, comprehensive research would be needed to clarify the specific study outcomes of this medication in managing IBS symptoms.

Acute Enterocolitis

The research base for using Donnatal in cases of acute enterocolitis—which involves a sudden inflammation of the small intestine and colon—is quite limited. Most of the evidence that has explored this use comes from older, observational reports or small studies rather than large, controlled clinical trials.

Research has explored whether it may affect the intense muscle spasms and painful cramping associated with gastrointestinal inflammation. Limited findings from the studies indicated changes in these specific spasm-related symptoms.

Given the serious nature of acute enterocolitis and the older, less formal structure of the available studies, significant uncertainty remains. There is a clear gap in robust, modern research specifically designed to assess the overall study outcomes of Donnatal in this acute condition. The current available evidence is insufficient to draw clear conclusions about the study outcomes beyond the reported influence on immediate spasm discomfort.

Frequently Asked Questions (FAQ)

Common questions about Donnatal (FAQ)

Q: How quickly does Donnatal typically start working for stomach issues?

A: Regulatory information indicates that the mild sedative component, phenobarbital, which is part of the Donnatal combination, is a long-acting substance. When administered alone, the onset of its effects is typically observed within 30 minutes after taking it. The specific time to effect for the full combination product can vary among individuals.

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

A: The duration of effect for the standard tablet or elixir is generally consistent with the phenobarbital component, which may last for approximately 5 to 6 hours. The extended-release form, known as Donnatal Extentabs, is specifically formulated to last longer, typically providing effects for up to twelve (12) hours.

Q: Is Donnatal considered a controlled substance?

A: Yes, Donnatal is officially classified by the Drug Enforcement Administration (DEA) as a Schedule IV (CIV) controlled substance. This classification is due to the presence of phenobarbital, which is known to carry a risk of dependence.

Q: Is it possible to develop a tolerance to the effects of Donnatal?

A: Official warnings state that both tolerance (a need for higher doses to achieve the same effect) and physical or psychological dependence can occur with the continued, repeated use of Donnatal. This risk is primarily associated with the phenobarbital ingredient.

Q: What is the official classification of Donnatal by the FDA?

A: The official classification of Donnatal is based on a review of evidence by the FDA. The agency has classified its use as an adjunctive (additional) therapy for irritable bowel syndrome and acute enterocolitis as 'possibly' effective based on the data available from studies.

Q: Does Donnatal have a black box warning?

A: While the official labeling does not explicitly use the term 'Black Box Warning,' it does detail serious safety considerations. These include the risk of dependence associated with phenobarbital and warnings about rare, potentially life-threatening skin reactions like Exfoliative dermatitis.

Q: How long does Donnatal stay in your system after stopping treatment?

A: The phenobarbital component is known to have a long half-life, which is the time it takes for half of the drug to be eliminated from the body. In adults, the half-life typically ranges from 53 to 118 hours. This means the drug can take several days to be fully cleared from the body after treatment has stopped.

Q: Why does Donnatal contain phenobarbital?

A: Donnatal is a combination product designed to offer both spasm relief and nervous system calming. The combination includes phenobarbital to provide mild sedation, which is intended to complement the antispasmodic effects of the belladonna alkaloids.

Q: Can Donnatal cause changes in vision?

A: Yes, the anticholinergic ingredients in Donnatal can lead to adverse reactions affecting the eyes. These documented effects include blurred vision, mydriasis (dilation of the pupils), and an increase in pressure within the eye, which is referred to as increased ocular tension.

Q: Are there any specific warnings about taking Donnatal if you have glaucoma?

A: Yes, Donnatal is officially contraindicated (should not be used) in patients with glaucoma. The anticholinergic effects of the medicine may increase pressure within the eye, which is why its use is restricted in this condition.

Q: Does Donnatal interact with alcohol?

A: Official information warns against combining this medication with alcohol. Taking Donnatal concurrently with alcohol or other central nervous system (CNS) depressants may result in additive depressant effects. The concurrent use of alcohol with Donnatal is noted to increase the risk of these effects.

Q: Does Donnatal make stomach bloating go away?

A: Official regulatory documents list a bloated feeling as a potential adverse reaction associated with the use of Donnatal. Because of this, the medication may not alleviate bloating for all users and, in some cases, may be associated with its occurrence.

Q: What type of research evidence supports the use of Donnatal for stomach spasms?

A: The primary official indication for Donnatal is as an adjunctive therapy for conditions like irritable bowel syndrome, which frequently involves stomach and bowel spasms. The evidence supporting its use for these symptoms has been reviewed, and the drug is officially classified as 'possibly' effective.

Q: Have there been any major studies on the long-term safety of Donnatal?

A: Official regulatory information states that long-term studies in animals have not been performed to evaluate the potential of Donnatal to cause cancer or genetic changes. This information is typically found in the safety sections of the drug label.

Q: Can Donnatal be taken with food, or does it need to be taken on an empty stomach?

A: General regulatory guidance for this class of medicine suggests taking it approximately 30 minutes to 1 hour before meals. This timing is generally noted to be optimal for the medication's action in the digestive tract.

Q: What are the rules about driving or operating machinery while on Donnatal?

A: Official labeling contains a specific warning that patients should not engage in activities that require full mental alertness while taking Donnatal. This includes operating a motor vehicle or other machinery if the medication causes side effects such as drowsiness or blurred vision.

Q: Can Donnatal affect the results of medical tests?

A: Official medical information indicates that Donnatal can affect the results of certain laboratory medical tests. The potential to affect test results highlights the importance of laboratory staff being aware if a patient is taking this medication.

Q: What should be done if an allergic reaction to Donnatal is suspected?

A: Official labeling describes signs of serious hypersensitivity reactions, which include swelling of the eyelids, cheeks, or lips, and severe skin reactions. The labeling describes these reactions as serious safety considerations that warrant immediate evaluation.

Q: Does Donnatal have any potential for misuse or dependence?

A: Yes, because Donnatal contains the barbiturate phenobarbital, it carries an inherent risk of both physical and psychological dependence. Regulatory warnings caution that the medication should not be given to individuals who are known to be prone to addiction.

Q: Can Donnatal be used for general stress or anxiety?

A: Official regulatory documents indicate that Donnatal is for adjunctive therapy for specified functional gastrointestinal disorders and is not indicated for general stress or anxiety alone.

Q: What are the specific conditions Donnatal is officially approved to treat?

A: Donnatal is officially approved for use as an additional (adjunctive) treatment for two specific conditions: irritable bowel syndrome (IBS) and acute enterocolitis (inflammation of the small and large intestines).

Q: What is the difference between Donnatal Elixir and the tablet form?

A: Both the liquid Elixir and the standard tablet contain the same fixed ratio of active ingredients. The Elixir form may be more suitable for patients who have difficulty swallowing tablets. A standard 5 mL teaspoonful of the Elixir contains the same amount of active drug as a standard tablet.

How should Donnatal be stored and disposed of?

How to Store and Dispose of Donnatal

Donnatal Tablets and Elixir must be stored at Controlled Room Temperature, specifically 20^circC to 25^circC (68^circF to 77^circF), with permitted excursions up to 30^circC. The medication must be protected from light and moisture; avoid freezing the product.

Tablets must be dispensed in a tight, light-resistant container utilizing a child-resistant closure. The Elixir container must be kept tightly closed and protected from physical damage.

All forms must be kept out of reach of children; the Elixir is explicitly instructed to be kept locked up. Disposal of unused Donnatal follows regulatory guidelines for non-flushable medicines, primarily recommending a drug take-back location or the approved household trash method.

Donnatal