Theo-24

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Choline Theophyllinate

Method of action: Antiallergic, Anti-Asthmatic, Antispasmodic, Bronchodilator, Cardiotonic, Diuretic, Drugs For Obstructive Airway Diseases, Vasodilator

Treatment option: Asthma, Bronchiolitis, Bronchitis, Bronchospasm, Respiratory Failure, COPD,Acute, Chronic Respiratory Failure, Emphysema

Medically reviewed

Rosario Oropesa

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 Theo-24

Property	Description
Active ingredient	Choline Theophyllinate (Oxtriphylline)
Form	Extended-Release Capsule/Tablet
Pharmacological class	Bronchodilator (Methylxanthine)
Common use	Managing chronic airway obstruction
Origin	Synthetic

What is Theo-24 and What Class of Medicine is it?

Theo-24 is a prescription-only medication that is classified as a bronchodilator, primarily used for the long-term management of chronic breathing disorders. The definitive classification for its core active component, Theophylline, is within the Methylxanthine pharmacological class. This class is clinically recognized for its efficacy in relaxing airway muscles. Theophylline is a synthetically derived Xanthine Derivative, chemically related to substances like caffeine.

The drug entity contains the active ingredient Choline Theophyllinate, also known as Oxtriphylline. This compound is a salt of the pharmacologically active Theophylline base, which functions as a respiratory smooth muscle relaxant to ease breathing difficulties.

The Role of Extended-Release Formulations

The key pharmaceutical characteristic of this oral medication is its long-acting nature, presented primarily as an Extended-Release Capsule or Extended-Release Tablet. This extended-release form is specifically engineered to control the rate at which the active component, Choline Theophyllinate, is released into the body.

This controlled delivery, which typically spans 12 or 24 hours, is crucial because it ensures sustained therapeutic levels of Theophylline within the body. Stable drug concentrations are required for continuous therapeutic benefit. Unlike medications designed for rapid, immediate action, the extended-release forms provide a smooth, consistent concentration of the drug, which is particularly beneficial for managing overnight symptoms.

General Purpose of this Long-Acting Bronchodilator

The general purpose of the medication is to maintain the function of the lungs by continuously acting as a smooth muscle relaxant on the tissue surrounding the bronchial airways. The mechanism involves multiple physiological actions, which collectively widen the air passages, a process known as bronchial dilation.

By preventing the constriction of the airway muscles and reducing the airways' tendency to tighten, this medication effectively relieves the persistent symptoms of obstructed breathing. Its long-acting profile is uniquely aimed at providing consistent, preventative support for patients dealing with chronic airway disease, such as those with Chronic Obstructive Pulmonary Disease (COPD).

What side effects are possible with Theo-24?

Possible Side Effects and Safety Information

The safety profile of Theo-24 (theophylline) is highly dependent on the amount of drug present in the blood. Adverse effects are generally mild when serum concentrations are below 20 mcg/mL, but the frequency and severity increase significantly when this level is exceeded, defining a narrow therapeutic range.

Key Adverse Reaction Categories

Adverse effects are documented across several body systems, with primary focus on Nervous System, Cardiovascular, and Gastrointestinal events. These effects may include headache, irritability, restlessness, insomnia, and tremors, as well as rapid or irregular heartbeats (sinus tachycardia).

Serious Adverse Reactions that are typically associated with high serum concentrations (toxicity) include seizures, persistent or intractable vomiting, and severe cardiac arrhythmias (such as ventricular arrhythmias).

Population-Specific Safety Considerations

The drug's clearance from the body can be significantly altered in specific populations, increasing the potential for toxicity. Infants and the elderly may be more sensitive to adverse effects, and patients with underlying conditions such as liver disease (e.g., cirrhosis), heart rhythm disorders, or active peptic ulcer disease require particular caution and monitoring. Numerous drug-drug and drug-substance interactions (e.g., smoking, concurrent medications) can unpredictably change the drug's concentration, underscoring the necessity for frequent serum level monitoring.

Overdose and Emergency Response

Overdose and When to Seek Help

The official regulatory profile for Theophylline (the active component in Theo-24) defines overdose as a serious, potentially life-threatening event.

Documented Manifestations and Severe Outcomes

Overdose manifestations are primarily systemic, affecting the cardiovascular, central nervous, and metabolic systems. Documented clinical signs include severe nausea and vomiting, seizure (convulsions), tremors, and agitations. Cardiovascular signs often include rapid heartbeat (tachycardia) and arrhythmias. A key indicator of toxicity is a serum theophylline concentration greater than 20 mcg/mL. Overdose-induced seizures and cardiac arrest are documented as potentially resulting in death or permanent brain damage. Due to the extended-release formulation, peak toxicity may be delayed.

Emergency Action and Monitoring

Regulatory documents mandate that patients must seek emergency medical attention immediately or contact the Poison Help line upon suspicion of overdose or symptom onset. Urgent medical help is required for life-threatening symptoms such as seizures or arrhythmias. Treatment outlined in regulatory documents is supportive, often requiring multiple-dose activated charcoal for gastrointestinal decontamination and intensive cardiac monitoring. Continuous observation and frequent testing of serum theophylline concentrations are necessary to guide the required supportive care.

Population-Specific Risks

The official labeling notes that toxicity can occur at lower drug concentrations in vulnerable groups, including the elderly, premature neonates, and patients with conditions such as hepatic cirrhosis or uncorrected acidemia.

Therapeutic Uses of Theo-24

What Theo-24 Treats — Main Uses and Benefits

Theo-24 (theophylline extended-release) is commonly used to help with symptoms related to chronic lung diseases. Specifically, it is relevant for conditions characterized by periods of heightened symptoms, such as chronic asthma, chronic bronchitis, and emphysema. Its use is aligned with therapeutic domains for which additional symptomatic support is needed for long-term supportive care to address symptoms related to physical discomfort that create noticeable physiological strain, such as wheezing and shortness of breath.

This medication generally provides sustained, around-the-clock support in managing symptoms associated with airflow changes that occur with these conditions. It offers symptomatic relief for the distressing manifestations of a chronic breathing disorder. It is considered relevant in contexts involving heightened systemic burden and may assist with maintaining a sense of stability during symptomatic periods. It contributes to easing the overall symptom load.

“The medication is commonly used to help address persistent, recurring breathing difficulties associated with long-term lung conditions.”

Quick Fact: Relief for Persistent Airway Symptoms

Regulatory References

Theophylline Extended-Release Tablets Rx only

Eligibility and Restrictions for Use

Eligibility Map: Who Can and Cannot Use Theo-24

This section outlines the official, regulatory-documented rules governing the use of Theo-24 (Theophylline Extended-Release) based strictly on governmental labeling.

Eligibility Scope

Category	Population Eligibility Rules
Populations Contraindicated	Patients with known hypersensitivity to Theophylline or any other xanthine derivative.
	Infants under 6 months of age (contraindicated by some regulators).
Age-Related Rules	Approved for use in adults and children aged 6 years and above; requires caution in older adult patients due to slower drug clearance.
Conditional Use	Use requires caution and close monitoring in patients with impaired liver function (hepatic impairment), severe hypertension, peptic ulcer disease, hyperthyroidism, and specific cardiac arrhythmias.
Reproductive Status	Pregnancy Category C, meaning use is conditional and restricted to cases where the potential benefit clearly outweighs the potential risk. Conditional use status for nursing mothers.

Summary of Restrictions

Regulatory documents define the scope of use by establishing absolute contraindications (allergy and infancy) and setting conditional restrictions for populations with altered drug metabolism or increased risk, such as those with hepatic impairment or heart conditions.

What should I know about interactions with other medicines?

Interactions with other medicines and products

The official regulatory profile for Theophylline (the active component of Theo-24) is structured around documented changes to its concentration and specific physiological effects. The concurrent use of other Xanthine drugs is strictly restricted due to the potential for additive toxicity. Co-administration with Riociguat is also generally not recommended.

Pharmacokinetic Interactions

Many interactions are classified based on the inhibition or induction of metabolic enzymes, primarily involving the CYP450 system, which alters Theophylline's clearance. Drugs such as Cimetidine and the antibiotic Ciprofloxacin are documented to decrease Theophylline clearance, resulting in officially increased plasma concentrations. Conversely, agents like Rifampicin and the supplement St. John's Wort are documented to increase clearance, resulting in lower drug exposure.

Pharmacodynamic and Other Interactions

Theophylline antagonizes the anti-arrhythmic effect of Adenosine. Co-administration with general anesthetics like Halothane is documented to increase the risk of ventricular arrhythmias. Additionally, smoking is officially documented to increase Theophylline clearance, while a single large dose of alcohol is documented to decrease clearance for up to 24 hours. Clearance is also significantly reduced in individuals with hepatic impairment, which increases the risk of concentration-related toxicity.

Mechanism of Action

Theo-24 works through two primary, non-selective pharmacodynamic actions that influence key physiological regulatory systems: enzyme inhibition and receptor antagonism. This dual mechanism affects core signaling patterns involved in modulating muscle tone and cellular excitability.

Phosphodiesterase Inhibition and Smooth Muscle Relaxation

Theophylline acts as an inhibitor of Phosphodiesterase (PDE) enzymes, specifically PDE3 and PDE4. This action decreases the hydrolysis of cyclic adenosine monophosphate (cAMP), increasing its intracellular concentration. This rise in cAMP is a crucial step in signaling cascades that lead to the relaxation of bronchial smooth muscle. The resulting physiological effect is bronchial smooth muscle relaxation, defined as bronchodilation.

Adenosine Receptor Antagonism and Systemic Stimulation

Theo-24 also acts as a non-selective antagonist on adenosine receptors in the central and peripheral nervous systems. By blocking the binding of the inhibitory neuromodulator adenosine, the drug initiates a cascade of effects leading to increased cellular excitability and stimulation. The physiological consequence of this antagonism includes stimulation of central respiratory drive and increased heart and muscle contractility. This mechanism also contributes to modulating inflammatory cell activity.

Dosage and Administration Information

How to Use Theo-24

Theo-24, the extended-release formulation of theophylline, is administered orally and is intended for long-term supportive care to manage chronic breathing conditions. The core principle of its use is maintaining a consistent therapeutic concentration of the drug over a 24-hour period.

Administration and Dosing Schedule

Administration typically follows a once-daily (Q24 hours) schedule, although a divided twice-daily dose may be used in some patients to ensure stable serum levels. Dosing is highly individualized and must be initiated with a starting dose, which is then gradually titrated (adjusted) upward to reach a defined maintenance range.

Feature	Procedural Guideline
Route & Form	Must be taken orally. The extended-release tablet or capsule must be swallowed whole and must not be crushed, chewed, or broken.
Timing	Should be taken at a consistent time each day. Administration should be synchronized with meals (either always with food or always without) to ensure predictable absorption.
Adult Dosing	The typical maintenance dose range for adults is generally 400 mg to 600 mg per day, with doses exceeding 600 mg requiring close monitoring.

Special Procedural Constraints

Use of Theo-24 necessitates the periodic measurement of serum theophylline concentrations; this mandated therapeutic drug monitoring guides any subsequent dose adjustments and is a necessary step in the official use protocol. For older adults (over 60), the starting dose and the maximum allowed daily dose are typically lower due to changes in drug clearance. If a dose is missed, the protocol involves taking it if remembered within approximately 4 hours of the scheduled time; otherwise, the missed dose should be skipped.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Theo-24 (Theophylline Extended-Release)

Evidence for Use in Chronic Obstructive Pulmonary Disease (COPD)

Research has explored theophylline extended-release by studying its use in the context of persistent airflow difficulties associated with Chronic Obstructive Pulmonary Disease (COPD). Randomized Controlled Trials (RCTs) were conducted, often comparing the medicine to a placebo or examining its use alongside other treatments. Researchers primarily monitored objective changes in lung function, such as measuring the volume of air a person can forcefully exhale in one second (FEV1), which helps indicate how much the airways may be restricted.

Studies reported measurable changes in lung function parameters observed during the research period. However, reported outcomes for subjective measures like dyspnea and exercise capacity were mixed across studies. Long-term studies, primarily observational in nature, were used to track outcomes like mortality, but these studies do not fully clarify whether the medicine was the only factor influencing these results.

Evidence for Use in Chronic Asthma

The extended-release formulation was studied for use as a long-term therapy for individuals with chronic asthma, particularly in contexts where symptoms may vary in intensity. Randomized Controlled Trials monitored outcomes related to lung function and symptom control, with a focus on patient-reported outcomes describing perceived discomfort, including nighttime breathing difficulties. Studies monitored how symptoms evolved in the observed populations and highlighted changes measured in objective lung function during the research period.

The evidence base for asthma contains limited information for long-term outcomes, as trials generally lasted for shorter to intermediate time frames. Some evidence regarding theophylline's use in asthma predates the widespread adoption of current standard inhaled therapies, which affects the contemporary relevance of the reported findings.

Evidence Gaps and Areas of Uncertainty

The medication's narrow therapeutic window (the range of concentration studied in the bloodstream) means the results apply only to the specific conditions under which they were conducted. The certainty remains low regarding the consistency of subjective patient-reported outcomes across all studies. Furthermore, comparative evidence is lacking against some of the more recently developed therapies. While studies contribute to the broader evidence landscape, they highlight what is known — and what is still uncertain — regarding long-term, sustained benefits and applicability to every possible patient group.

Key Studies & References

Frequently Asked Questions (FAQ)

Common questions about Theo-24 (FAQ)

Q: Is it normal to feel a slightly faster heart rate when starting Theo-24?

A: According to official product information, tachycardia (a faster or rapid heartbeat) is a commonly reported side effect of theophylline. As Theo-24 is a stimulant, this effect is often mild at proper therapeutic concentrations. However, if heart palpitations or a very irregular heart rhythm become severe, it may be a sign of the drug concentration being too high.

Q: How long does a single dose of Theo-24 stay in your system?

A: The time it takes for Theo-24 to be cleared from the body is highly variable between individuals. The half-life (the time required for the body to eliminate half of the drug) can range approximately from 4 to 13 hours in non-smoking adults. This elimination rate can be affected by factors like age, smoking status, and other health conditions.

Q: Does taking Theo-24 with caffeine cause more side effects?

A: Theo-24 belongs to the methylxanthine class, the same chemical family as caffeine. Regulatory documents note that combining the two may result in additive stimulant effects or increase the risk of theophylline-related side effects, such as nervousness and insomnia.

Q: How often do people typically need to get blood tests while on Theo-24?

A: Treatment with Theo-24 requires mandatory periodic monitoring of the drug concentration in the blood, often referred to as Therapeutic Drug Monitoring (TDM). This monitoring is essential due to theophylline's narrow therapeutic range. The frequency of these required blood tests is highly individualized and determined by the healthcare provider to ensure concentrations remain within the target range.

Q: Can children or adolescents use Theo-24 for breathing problems?

A: Official information states that Theo-24 is approved for use in adults and children aged 6 years and older. Dosing for children and adolescents is highly specific and requires careful determination and monitoring by a healthcare provider.

Q: Are there any foods or drinks I should completely avoid while taking Theo-24?

A: Regulatory documents highlight interactions with alcohol, particularly acute large doses, which can affect the body's clearance of the drug. Additionally, because theophylline is chemically related to caffeine, limitations on caffeine intake may be necessary due to the potential to increase stimulant-related side effects.

Q: What are the most common reasons a doctor might prescribe Theo-24?

A: Theo-24 is indicated for the long-term management of breathing conditions. Specifically, it is used to treat the symptoms of chronic asthma and reversible bronchospasm associated with Chronic Obstructive Pulmonary Disease (COPD).

Q: Can Theo-24 help with asthma symptoms, or is it only for COPD?

A: Official indications confirm that Theo-24 is used for the management of symptoms associated with both chronic asthma and the reversible airway obstruction seen in COPD.

Q: What happens if I accidentally miss a dose of Theo-24?

A: General regulatory guidance addresses missed doses. Patients should follow the specific directions provided by their healthcare professional. Typically, if a dose is missed, professional guidance is needed to determine the appropriate time to take it or if it should be skipped.

Q: Is it possible for Theo-24 to interfere with my sleep?

A: Yes, insomnia (difficulty falling or staying asleep) is a documented adverse reaction associated with theophylline. This is attributed to the drug’s central nervous system (CNS) stimulating properties.

Q: Does Theo-24 interact with common cold and flu medications?

A: Theo-24 is known to interact with many different types of medications. This includes certain antibiotics often prescribed for secondary infections, such as ciprofloxacin, which can increase theophylline levels. Additionally, ingredients like ephedrine or other stimulants sometimes found in cold remedies can have additive effects.

Q: Why do some people experience nausea or stomach upset with Theo-24?

A: Nausea and vomiting are commonly reported gastrointestinal adverse reactions. Official safety information notes that the frequency and severity of these symptoms increase if the drug concentration in the blood rises above the therapeutic range.

Q: What are some less common side effects of Theo-24 I should be aware of?

A: Documented less common adverse effects include dizziness, diarrhea, palpitations (irregular or forceful heartbeats), and irritability. Severe reactions, such as seizures or severe heart rhythm disturbances, are typically associated with high, toxic concentrations of the drug in the bloodstream.

Q: What is the therapeutic window for theophylline and why is it important?

A: Theophylline is described as having a narrow therapeutic range or window. This means there is a small difference between the concentration that is effective (therapeutic) and the concentration that is likely to cause toxicity. The target concentration range is narrow, which makes careful dosage adjustment and blood monitoring essential to ensure safety and effectiveness.

Q: Does taking Theo-24 require changes to my diet?

A: Consistent use requires that Theo-24 be taken in a consistent manner relative to meals (for example, always with food or always without) to ensure the extended-release formulation is absorbed predictably. Acute changes in diet, such as consuming a single large dose of alcohol, are documented to affect how the body processes the drug and may require professional guidance.

Q: Why is it important to take Theo-24 at the same time every day?

A: Taking the medication at a consistent time each day is important because Theo-24 is designed to release slowly and continuously over a 24-hour period. This consistent timing helps to maintain the necessary stable serum concentrations that provide continuous, preventative support for chronic breathing difficulties.

Q: Can taking certain antibiotics change the effect of Theo-24?

A: Yes, regulatory documents note that many antibiotics can affect Theo-24 levels. For instance, specific drugs like ciprofloxacin and erythromycin are known to slow down the body's clearance of theophylline, which can lead to higher concentrations and a potential risk of toxicity.

Q: Is Theo-24 used for treating bronchitis?

A: Theo-24 is indicated for the treatment of reversible bronchospasm associated with chronic conditions like COPD. While it helps relieve the symptoms of obstructed breathing, the official label does not specifically list acute or chronic bronchitis as a primary indication.

Q: Can Theo-24 cause anxiety or nervousness?

A: Yes, due to its properties as a central nervous system (CNS) stimulant, nervousness, restlessness, and irritability are documented adverse reactions listed in official product information.

Q: Are there any herbal supplements or vitamins that interact with Theo-24?

A: Yes, official drug interaction information specifically lists the herbal supplement St. John's Wort. This supplement is documented to increase the body's clearance of theophylline, which could potentially lead to lower drug levels and reduce the overall effectiveness of Theo-24.

Q: What if I see what looks like the pill shell in my stool after taking Theo-24?

A: The extended-release formulation often uses a non-absorbable casing or matrix to ensure the drug is released slowly over time. Regulatory patient information states that it is not uncommon to see the empty, intact tablet casing or matrix shell pass through and appear in the stool after the active medication has been released and absorbed.

Q: What should I do if my breathing problems get worse while on Theo-24?

A: Regulatory guidance indicates that patients should seek prompt professional medical attention if breathing difficulties worsen or do not improve while using the medication.

Q: Is Theo-24 a medication that I have to take long-term?

A: Yes, Theo-24 is officially indicated for the long-term supportive care and maintenance treatment of chronic asthma and reversible bronchospasm associated with COPD.

Q: Can a thyroid condition affect how Theo-24 works?

A: Patients with an overactive thyroid (hyperthyroidism) may require special monitoring. Official information documents that this condition can increase the speed at which theophylline is cleared from the body, which may affect its concentration.

Q: Does body weight or obesity affect the required dosage of Theo-24?

A: Dosage determination for theophylline often relies on a patient’s lean body weight. This is because the drug does not readily distribute into fat tissue, and the appropriate starting dose must be determined by a healthcare provider.

Q: Why is theophylline considered a narrow therapeutic index drug?

A: Theophylline is considered a narrow therapeutic index drug because the difference between the drug concentration that works effectively and the concentration that causes significant side effects is small. This requires frequent monitoring of blood levels to ensure safety and effectiveness.

Q: Is it normal to feel dizzy or lightheaded sometimes while taking Theo-24?

A: Dizziness and lightheadedness are documented adverse reactions that can occur with theophylline.

Q: Can Theo-24 affect the results of other medical lab tests?

A: Official information indicates that theophylline may potentially interfere with certain laboratory tests used to measure other methylxanthine drugs in the body. This possible interference may lead to inaccurate results for those specific tests.

Q: Why is the release mechanism of Theo-24 important for its effect over 24 hours?

A: The extended-release mechanism is important because it ensures a slow, consistent delivery of the medication over a full 24-hour period. This sustained release is necessary to maintain stable therapeutic concentrations in the blood, which provides continuous, preventative symptom control.

Q: Is Theo-24 the same drug as the old-fashioned aminophylline?

A: The active component in Theo-24 is theophylline. While aminophylline is another compound (an ethylenediamine salt) that also contains the active theophylline component, they are not chemically identical drugs. Their properties and concentration of the active component may differ.

Q: What are the risks of using Theo-24 during pregnancy or while breastfeeding?

A: Theo-24 is classified as Pregnancy Category C, meaning potential risk to the fetus cannot be ruled out, and its use is limited to cases where the benefit outweighs the potential risk. Theophylline is also known to be excreted in human breast milk, requiring careful consideration for nursing mothers.

Q: Does Theo-24 interact with common medications for acid reflux?

A: Official interaction information documents that an older medication used for acid reflux, Cimetidine (an H2-blocker), can significantly slow the body's clearance of theophylline. This interaction can lead to increased concentrations of Theo-24 in the blood.

How should Theo-24 be stored and disposed of?

How to Store and Dispose of Theo-24

Theo-24 (theophylline extended-release) must be stored strictly according to regulatory mandates to maintain its stability.

Storage Requirements

Condition	Requirement
Temperature Range	Store at Controlled Room Temperature, 20^circ to 25 C (68^circ to 77 F).
Protection	Keep the product protected from both light and moisture.
Container	Must be stored in the original, tightly closed container.
Safety	Keep the medication stored out of the sight and reach of children.

Disposal Instructions

The preferred method for disposal of unused or expired Theo-24 is to use a local or national drug take-back program. If a take-back program is unavailable, the official guidance requires the product to be mixed with an undesirable substance, placed into a sealed container, and disposed of in the household trash. It is explicitly instructed not to flush this medication down the toilet.

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

Available in countries:

USA

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