Ultralax

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Ultralax

Method of action: Laxative

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 Ultralax

What is Ultralax? Defining the Stimulant Laxative

Property Description
Active Ingredient Bisacodyl
Form Oral Tablets (Enteric-coated), Rectal Suppositories
Pharmacological Class Stimulant Laxative / Contact Laxative
General Purpose Relief of Constipation
Origin Synthetic Substance (Diphenylmethane Derivative)

What Type of Medicine is Ultralax (Bisacodyl)?

Ultralax is a pharmaceutical entity defined by its sole active ingredient, Bisacodyl, which places it within the high-level pharmacological class of Laxatives. It is specifically identified as a Stimulant Laxative or Contact Laxative, a classification characterized by increasing activity of the intestines. The Bisacodyl substance is a synthetic substance derived from the Diphenylmethane derivative chemical structure. This dedicated formulation differentiates it from combination products, focusing its function on a predictable, direct mechanism for promoting a bowel movement.

Forms of Ultralax and Its Core Purpose

Ultralax is typically available as Oral Tablets and Rectal Suppositories, facilitating administration via the oral and rectal route, respectively. The tablet form is generally an enteric-coated dosage form, a unique characteristic designed to ensure the medicine remains intact until it reaches the lower digestive tract. This structural feature is crucial for targeted action in the colon, where it works by increasing peristalsis and fluid in the colon lumen. The core purpose of the drug is utilizing this specific stimulant laxative action to rapidly address general constipation or achieve efficient bowel evacuation when required.

Regulatory References

  1. clinically recognized by the NIH for increasing activity of the intestines
  2. according to research compiled by the FDA
  3. Bisacodyl
  4. Stimulant Laxative
  5. Constipation

What side effects are possible with Ultralax?

Possible Side Effects and Safety Information

The official safety profile for the active ingredient Bisacodyl (Ultralax) is established through structured reporting in government regulatory documents, classifying known adverse reactions based on frequency and affected system.

Adverse Reaction Classifications

The most frequently reported effects relate to the Gastrointestinal Disorders system. These effects are often localized and include abdominal pain and abdominal cramps, which are generally classified as Common in regulatory frequency frameworks (occurring in 1% to 10% of users).

Uncommon adverse reactions (occurring in 0.1% to 1%) may include vomiting, dizziness, abdominal discomfort, and haematochezia (blood in stool).

Serious Adverse Reactions and Safety Patterns

Rare adverse reactions (occurring in 0.01% to 0.1%) are documented and include serious events such as anaphylactic reactions, angioedema, colitis (including ischaemic colitis), and severe dehydration.

Safety notes specify that dizziness and syncope may occur, often representing a vasovagal response related to straining during the bowel movement, rather than a direct drug effect. Prolonged or excessive daily use of the medicine is associated with risks including fluid and electrolyte imbalance, specifically low potassium levels (hypokalaemia).

Safety Constraints and Considerations

The medicine is contraindicated in the presence of acute abdominal conditions such as intestinal obstruction (ileus), acute inflammatory bowel diseases, or severe dehydration. Specific safety considerations apply to pediatric patients and older adults; official labeling generally advises against use in children under 12 without professional advice, and monitoring is important for older patients at risk of dehydration. Additionally, the tablet form should not be taken within one hour of milk or antacids, as this may prematurely dissolve the enteric coating and cause gastric irritation.

Overdose and Emergency Response

Overdose and when to seek help

Overdose involving Bisacodyl (Ultralax) is officially documented following acute high-dose ingestion or chronic excessive use, leading to an exaggerated laxative effect. Acute presentation may include severe diarrhoea, vomiting, nausea, and intense abdominal cramps, resulting in clinically significant loss of water and electrolytes.

Regulatory sources identify several severe outcomes tied to this fluid loss, particularly severe dehydration and dangerous hypokalaemia (low potassium). Hypokalaemia can lead to muscular weakness and cardiac complications, specifically documented as ECG alterations. Chronic abuse may lead to long-term consequences, including secondary hyperaldosteronism, metabolic alkalosis, and renal tubular damage.

Immediate medical attention must be sought for any suspected overdose. Emergency services should be contacted if the person exhibits signs of systemic failure, such as collapse, a seizure, or an inability to be awakened. Treatment is supportive, focusing on the replacement of fluids and the correction of electrolyte imbalances. These corrective measures are explicitly noted as being especially important in the elderly and the young. Minimizing absorption via gastric lavage or activated charcoal may be considered in acute oral overdose situations.

Therapeutic Uses of Ultralax

What Ultralax Treats: Main Uses and Benefits

Ultralax is applied in contexts where supportive symptomatic management is appropriate. Bisacodyl is commonly used on a short-term basis to help with constipation and to empty the bowels before surgery and certain medical procedures.

The medication assists with managing symptom clusters that may appear suddenly, including infrequent bowel movements, significant straining, and the passage of hard or dry stools. It is relevant in conditions characterized by periods of heightened symptoms and is applied across domains where additional symptomatic support is needed.

The therapeutic benefit is relevant for patients experiencing acute or episodic difficulty. The medication contributes to bowel evacuation, which may help to ease the discomfort associated with stasis. This is relevant in clinical scenarios such as managing drug-induced constipation or supporting patients during the post-operative phase where avoiding straining is important.

Addressing Therapeutic Domains

This medicine is generally used for conditions presenting with acute or episodic manifestations, including general functional constipation, constipation associated with certain medications, and as supportive preparation for diagnostic or surgical procedures.


Quick Fact: Provides supportive relief for Acute Symptomatic Constipation


Regulatory References

  1. Bisacodyl: MedlinePlus Drug Information

Eligibility and Restrictions for Use

Official Regulatory Eligibility and Contraindications

Ultralax (referencing the regulatory profile of sodium phosphate laxatives) is subject to strict eligibility rules based on age, pre-existing conditions, and physiological status.

Contraindications (Must Not Use):

  • Age: Rectal administration is contraindicated in children younger than two years of age.
  • Gastrointestinal Conditions: Individuals with bowel obstruction, bowel perforation, toxic megacolon, toxic colitis, or active inflammatory bowel disease must not use this medicine.
  • Renal/Systemic Conditions: Use is prohibited for patients with pre-existing kidney disease or severe renal impairment, a history of acute phosphate nephropathy, or a known hypersensitivity to any product component.

High-Risk Populations (Requires Professional Consult):

Certain populations are at increased risk for serious electrolyte imbalances and kidney injury, and should consult a healthcare professional before use. These include individuals 55 years of age or older, patients with a sodium-restricted diet, those with heart conditions (e.g., heart failure), or anyone who is dehydrated or may be predisposed to electrolyte abnormalities.

Restriction: Do not use this medicine if you have already taken another product containing sodium phosphate.

What should I know about interactions with other medicines?

Interactions with other medicines and products

The following section outlines documented interactions between Ultralax and other substances, strictly based on official regulatory labeling. This information details which combinations require caution or are restricted due to specific effects on safety and efficacy.

Documented Interaction Categories

Category
Pharmacodynamic Interactions (Electrolyte Risk)
Reduced Efficacy Interactions (Bacterial Activation)
Oral Drug Absorption Interference

Clinically Significant Interactions

Official regulatory documents identify several categories of interacting agents:

  • Diuretics and Corticosteroids: Co-administration with thiazide or loop diuretics or corticosteroids increases the risk of hypokalemia (low potassium). This is a pharmacodynamic interaction based on fluid and electrolyte loss.
  • Cardioactive Glycosides (e.g., Digoxin): The risk of toxicity from agents such as digoxin is significantly increased if hypokalemia occurs as a result of taking Ultralax with diuretics or corticosteroids.
  • Broad-Spectrum Oral Antibiotics: These medicines may reduce the intended effect of Ultralax by inhibiting the colonic bacteria required to convert the inactive drug form into its active substance.
  • Other Oral Medicines: To ensure adequate systemic absorption of co-administered oral medications, the label requires a time-separation of at least two hours between taking Ultralax and these other medicines.
  • Other Stimulant Laxatives/Purgatives: The combination is restricted due to the potential for excessive gastrointestinal effects and severe electrolyte imbalance.

This profile defines specific constraints related to hypokalemia risk, drug efficacy, and absorption interference.

Mechanism of Action

How Ultralax Works

Ultralax (Bisacodyl) exerts a dual, localized action mediated by its active metabolite, BHPM (Bis-(p-hydroxyphenyl)-pyridyl-2-methane), which targets the colonic enteric neurons and epithelial cells.


Promoting Propulsive Motility

The BHPM metabolite acts as a chemical stimulant upon the Enteric Nervous System (ENS), specifically the parasympathetic nerve endings within the colonic wall. This interaction enhances neural signaling, which triggers strong, coordinated muscle contractions known as peristalsis. The resultant physiological modulation is an acceleration of intestinal content transit through the large intestine, increasing propulsive force.


Modulating Colonic Fluid Dynamics

Simultaneously, the active metabolite engages key signaling pathways in the colonic lining, involving the activation of the cAMP cascade and the downregulation of Aquaporin-3 (AQP3) water channels. This action reverses the net fluid transport mechanism: it drives the active secretion of electrolytes and water into the lumen while inhibiting water reabsorption back into the bloodstream. This modulation increases the volume and water content of the colonic contents.

Dosage and Administration Information

How to Use Ultralax: Official Administration Guidelines

Ultralax (Bisacodyl) is administered according to specific guidelines, primarily involving two distinct routes of administration with specific dosage schedules. The medication is intended for short-term use and should not be administered continuously for more than five to seven days, a constraint emphasized in prescribing information.


Administration Routes and Dosing

The medicine is available as a 5 mg delayed-release oral tablet and a 10 mg rectal suppository. Dosage depends on the administration route and the patient's age.

Administration Route Standard Adult Dose (ge 12 years) Key Timing Principle
Oral Tablet 5 mg to 15 mg in a single daily dose Taken at night for an effect 6 to 12 hours later.
Rectal Suppository 10 mg in a single daily dose Taken for a rapid effect, typically 10 to 45 minutes.

Preparation and Administration Constraints

The oral tablets are enteric-coated and must be swallowed whole with water; they are strictly not to be chewed or crushed. The integrity of this coating is essential, which is why the tablets must not be taken within one hour of consuming milk, antacids, or proton pump inhibitors (PPIs). For pediatric use, children aged 6 to under 12 years are given a lower, single daily dose of 5 mg, either orally or rectally, while administration to children under 6 requires consultation.

Recent Clinical Evidence

The clinical evaluation of Ultralax (Bisacodyl) has been conducted through formal research to understand its influence in specific, approved medical contexts. The findings describe group patterns observed in these studies and do not determine whether an individual will respond similarly.


Evidence for Use in Functional and Chronic Constipation

Evidence derived from randomized controlled trials (RCTs) and systematic reviews explored whether Ultralax influenced defined study outcomes of bowel function, such as the frequency of bowel movements and associated symptoms in adults. Studies were concerned with outcomes related to physical discomfort and functional imbalance, such as the number of weekly bowel movements, and whether the research measured a change in stool consistency.

Data show patterns related to measurements of greater average weekly bowel movements in the groups receiving the active ingredient compared to placebo. Systematic reviews summarized findings suggesting a higher proportion of patients reported three or more weekly bowel movements compared to placebo. However, certainty remains low regarding the consistency of results when Bisacodyl is compared against different, non-stimulant laxative treatments.


Evidence for Use in Bowel Evacuation for Medical Procedures

The structure of clinical trials and meta-analyses has examined the role of Bisacodyl as a component of the bowel preparation regimen required before diagnostic procedures like colonoscopy. Comparative clinical trials primarily assessed the Quality of Bowel Preparation and monitored patient-reported outcomes describing perceived discomfort.

Data show patterns related to preparation quality where Bisacodyl was studied for its use as a component in lower-volume preparation regimens. Findings indicate that some of these combination regimens were associated with observed patterns in patient tolerance. The usefulness in this context was observed almost exclusively when Ultralax is used as part of a multi-drug regimen.


Evidence in Specific Patient Populations

Research has explored the use of Bisacodyl in study populations that include older adults and the pediatric population. The findings related to observed patterns of change or tolerance specifically for older adults may be uncertain. Similarly, the data for certain pediatric groups remain insufficient, especially compared to the extensive trial data available for adults.


What is Still Uncertain About Ultralax Research

Some areas of uncertainty remain. Comparative evidence is lacking in high-quality randomized trials against many newer treatments. Furthermore, sample sizes were modest in some older studies, and there is limited information for long-term outcomes regarding the maintenance of change beyond the first month of treatment.

Key Studies & References

  1. Bisacodyl: MedlinePlus Drug Information
  2. Clinical evaluation and regulatory status of Bisacodyl for the treatment of chronic constipation: A systematic review and meta-analysis of RCTs

Frequently Asked Questions (FAQ)

Common questions about Ultralax (FAQ)

Q: Does Ultralax cause dependency if used frequently?

Official regulatory information for stimulant laxatives notes that continuous, daily use over a prolonged period is associated with a risk of harming normal intestinal function.

This excessive use can also lead to fluid and electrolyte imbalances, such as low potassium levels (hypokalemia). For this reason, official labeling notes that the medicine should be limited to short-term use, generally no more than five to seven days.


Q: Can Ultralax affect the absorption of my vitamins or supplements?

Yes, regulatory information advises that Ultralax tablets can affect the absorption of other oral medicines, including vitamins and supplements.

To ensure adequate systemic absorption of these products, regulatory labeling indicates that they should be taken at least two hours apart from the Ultralax tablet.


Q: Are there any specific foods I should avoid when taking Ultralax?

According to the official product information, the oral tablet should not be consumed within one hour of consuming milk or antacids.

This is a requirement because milk or antacids can cause the protective enteric coating of the tablet to dissolve prematurely, potentially leading to gastric irritation.


Q: Does Ultralax interact with blood pressure medications?

Official documents describe interactions where co-administration with diuretics or corticosteroids increases the risk of hypokalemia, or low potassium.

The interaction is based on an increased risk of hypokalemia (low potassium) when combined with diuretics or corticosteroids, which are listed in the regulatory documents.


Q: Can I take Ultralax if I have an existing bowel condition like IBS?

Official regulatory documentation strictly contraindicates the use of this medicine in the presence of acute abdominal conditions.

Examples of these conditions include intestinal obstruction, acute inflammatory bowel diseases, or severe dehydration. The information does not, however, list every non-acute bowel condition.


Q: Is Ultralax typically taken on an empty stomach or with food?

The oral tablet is designed with an enteric coating and is intended to work locally in the large intestine.

Because its effect is independent of the digestive process in the small intestine, official labeling focuses on avoiding consumption with milk or antacids, rather than specifying general food requirements.


Q: What is the purpose of the non-active ingredients listed for Ultralax?

The non-active ingredients, or excipients, are included to ensure the product's overall stability, shape, and targeted function.

For example, the enteric coating is one such non-active ingredient that is essential for preventing the medicine from dissolving in the stomach before it reaches the area where it is designed to work.


Q: Do patient reports often mention nausea as a side effect of Ultralax?

Yes, official regulatory documents list nausea as a common gastrointestinal side effect of this medicine.

Common side effects are those that are reported to occur in a frequency range of 1% to 10% of users.


Q: Can Ultralax be taken with iron supplements?

As with many oral medicines, regulatory labeling requires iron supplements to be taken at a different time than Ultralax tablets.

Official labeling requires a time-separation of at least two hours between taking Ultralax and iron supplements to ensure adequate systemic absorption of the supplement.


Q: What should I do if I miss a dose of Ultralax?

Regulatory information notes that because this medication is commonly used on an 'as-needed' basis, a standard scheduled missed dose instruction may not be applicable.

For individuals following a regularly scheduled treatment plan, the guidance is generally to take the dose when remembered, unless it is close to the time for the next scheduled dose, in which case the missed dose should be skipped.


Q: Is Ultralax safe to take while breastfeeding, according to official documents?

Studies cited by authoritative health bodies, such as the NIH, have indicated that the active metabolite of Bisacodyl is not detectable in human breast milk.

Based on this evidence, and official information indicates that use during breastfeeding does not require special precautions.


Q: How long does the effect of Ultralax typically last?

Clinical trial data provides insight into the duration of the physiological effects of the medicine.

Findings indicated that after treatment was ceased, the drug’s influence on the underlying physiological changes promoted in the colon returned to baseline values within 24 hours.


Q: Is it normal if Ultralax doesn't seem to work the first time I take it?

Official safety information includes a caution that individuals should stop use and consult a health professional if they fail to have a bowel movement after using a laxative.

This guideline exists because a failure to produce a bowel movement may be an indication of a more serious, underlying condition.


Q: Does Ultralax contain gluten or common allergens?

Official product labeling contains a full list of all inactive ingredients, which may include substances like corn starch or anhydrous lactose.

However, the regulatory documents do not provide a specific certification or statement regarding the product's gluten content or its status concerning common allergens.


Q: Can pregnant individuals take Ultralax?

Official labeling generally states that consultation with a health professional is advised before using this medication during pregnancy.

This consultation is advised before initiating use during the pregnancy period.


Q: Are there any known interactions between Ultralax and alcohol?

Information provided by government health authorities indicates that there is no known interaction between this medicine and alcohol.

Therefore, a specific warning regarding alcohol is not present in official labeling.


Q: Does taking Ultralax affect laboratory blood tests?

The known side effects associated with prolonged or excessive use include an increased risk of hypokalemia, or low potassium levels.

Since hypokalemia is an electrolyte imbalance, this effect may be reflected in routine laboratory blood test results.


Q: What are the signs of taking too much Ultralax?

Signs of taking too much of a laxative, according to government medical sources, often include symptoms like nausea, vomiting, stomach cramping, and diarrhea.

Severe or prolonged symptoms may lead to dehydration or electrolyte imbalance, effects that are typically regarded as serious.


Q: Is Ultralax absorbed into the bloodstream?

The medicine is designed to have a localized action within the colon.

Official documents indicate that absorption from the gastrointestinal tract is minimal. Any small amount that may be absorbed into the system is then typically excreted.


Q: Can I use Ultralax if I am a vegetarian or vegan?

Official product information provides a full list of all inactive ingredients, which may include substances such as gelatin or anhydrous lactose.

The full inactive ingredient list may contain non-plant-derived components, and individuals on a strict vegetarian or vegan diet often review this information.

How should Ultralax be stored and disposed of?

How to Store and Dispose of Ultralax?

The storage and disposal of Ultralax (Bisacodyl) must adhere strictly to official regulatory requirements to maintain product stability and ensure safety.


Storage Conditions

Ultralax must be stored at Controlled Room Temperature, defined as 20 C to 25 C (68 F to 77 F). The product must be protected from light and excessive humidity. It is required to be kept in a tight, light-resistant container with a child-resistant closure.

Child-Safety and Handling

For safety, the medicine must be stored out of the sight and reach of children.

Disposal Instructions

Unused or expired Ultralax should preferably be taken to an official drug take-back program. If this option is unavailable, the medicine must be mixed with an undesirable substance (e.g., dirt, coffee grounds) in a sealed bag before being placed in household trash, according to federal guidance. All personal information on the container must be scratched out prior to disposal.

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

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