Theo-24 (Theophylline) - Oral

What Is Theo-24?

Theo-24 (theophylline) is an oral prescription drug used to treat symptoms of asthma and reversible airflow obstruction due to chronic asthma and chronic obstructive pulmonary disease (COPD). COPD includes emphysema and chronic bronchitis.

As a bronchodilator, Theo-24 works by relaxing the smooth muscle of the airways to open air passages into the lungs, making it easier to breathe. It also reduces inflammation and airway reactivity to stimuli, like allergens, that may lead to wheezing or shortness of breath. Theophylline is in a drug class called methylxanthines.

Theo-24 is available as an extended-release capsule. Theophylline can also be dosed intravenously, but this article focuses on the oral version.

Drug Facts

Generic Name: Theophylline

Brand Name(s): Theo-24

Drug Availability: Prescription

Administration Route: Oral

Therapeutic Classification: Bronchodilator

Available Generically: Yes

Controlled Substance: N/A

Active Ingredient: Theophylline

Dosage Form(s): Oral

What Is Theo-24 Used For?

The Food and Drug Administration (FDA) approved Theo-24 to treat symptoms and airflow obstruction due to chronic asthma and COPD, including emphysema and chronic bronchitis.

Bronchodilators are commonly used as maintenance and rescue therapy in people with COPD and chronic asthma. However, they are usually just one part of a combined strategy for managing these conditions. The overall goal of treatment for COPD is to reduce symptoms, prevent worsening, and decrease mortality, and the goal for asthma is to reduce inflammation and achieve symptom control.

Theophylline has been around for decades but has fallen out of favor due to its side effects. With the availability of more effective and safer bronchodilators, theophylline is not recommended as a first-choice therapy. Theophylline will typically only be prescribed if other therapies do not work or cause intolerable side effects.

How to Take Theo-24

If you are prescribed Theo-24, read the prescription label and the information leaflet that comes with your prescription. Consult your healthcare provider if you have any questions.

Use this medication as directed, and do not skip doses. Do not take Theo-24 in larger amounts than prescribed or for longer than prescribed. Do not change your dose or dosing schedule unless instructed by your healthcare provider.

Take Theo-24 in the morning, at about the same time every day. Swallow the capsules whole; do not cut, crush, or chew them. It is not a rescue medication; if you have an asthma or bronchospasm attack, use your fast-acting rescue inhaler as directed by your healthcare provider and seek immediate medical help if your breathing worsens.

Storage

Store it at room temperature (68 to 77 degrees Fahrenheit), away from heat, direct light, and moisture. Keep this medication in its original labeled container and out of the reach and sight of children and pets. Keep the bottle tightly closed when not in use.

Off-Label Uses

Sometimes Theo-24 is used off-label for indications that are not FDA approved. Healthcare providers may prescribe Theo-24 to treat sleep apnea in people with systolic dysfunction due to chronic heart failure if other therapies have not worked.

Multiple clinical studies have suggested that oral theophylline therapy can reduce sleep-disordered breathing episodes in this population. However, the researchers noted that part of the improvement may be due to the deterioration in sleep quality. Still, it is sometimes considered for use if other therapies have not worked.

How Long Does Theo-24 Take to Work?

Theo-24 is an extended-release capsule, which allows dosing every 24 hours. Theo-24 works when taken daily as preventive therapy. It does not treat acute attacks.

What Are the Side Effects of Theo-24?

Like other medications, Theo-24 can cause side effects. Tell your healthcare provider about any side effects you experience while taking this medication.

This is not a complete list of side effects, and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your healthcare provider. You may report side effects to the FDA at fda.gov/medwatch or 1-800-FDA-1088.

Common Side Effects

The most common side effects of Theo-24 are the following:

  • Stomach problems, such as nausea, vomiting, and diarrhea
  • Headache 
  • Insomnia (trouble sleeping)
  • Irritability 
  • Restlessness
  • Tremor (involuntary shaking or movement)
  • Increased urination

Severe Side Effects

Call your healthcare provider immediately if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects can include the following:

  • Seizures 
  • Arrhythmia (irregular heartbeat)
  • Hypotension (low blood pressure)
  • Shock (drop in blood flow when the body is not getting enough oxygen)
  • Exfoliative dermatitis with redness, inflammation, and peeling of the skin

Long-Term Side Effects

While many people tolerate Theo-24 well, long-term or delayed side effects are possible. Some long-term side effects can be mild:

Moderate long-term side effects can include the following: 

  • Contact dermatitis can manifest as a red, itchy skin rash.
  • Hypercalcemia (too much calcium in the blood)
  • Metabolic acidosis (too much acid in the body) can cause symptoms like nausea, vomiting, tiredness, and fast breathing.
  • Low potassium levels with symptoms such as constipation, fatigue, numbness and tingling, and muscle weakness
  • High blood sugar with symptoms such as increased thirst, hunger, and urination

Severe long-term side effects may include these:

  • Exfoliative dermatitis
  • Vomiting blood
  • Seizures
  • Rhabdomyolysis (a life-threatening condition due to muscle breakdown)

Report Side Effects

Theo-24 may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your healthcare provider may send a report to the FDA's MedWatch Adverse Event Reporting Program online or by phone (800-332-1088).

Dosage: How Much Theo-24 Should I Take?

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The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • To treat symptoms of asthma, bronchitis, and emphysema:
    • For oral dosage form (elixir or tablets):
      • Adults, teenagers, and children above 1 year of age weighing more than 45 kilograms (kg)—At first, 300 milligrams (mg) per day, divided and given every 6 to 8 hours. Your doctor may adjust your dose as needed. However, the total dose is usually not more than 600 mg per day.
      • Older adults—The dose must be determined by your doctor. However, the total dose is usually not more than 400 milligrams per day, divided and given every 6 to 8 hours.
      • Children and teenagers 1 to 15 years of age weighing less than 45 kilograms (kg)—Dose is based on body weight and must be determined by your doctor. At first, the dose is 12 to 14 milligrams (mg) per kg of body weight per day, divided and given every 4 to 6 hours. Your doctor may adjust your dose as needed. However, the total dose is usually not more than 20 mg per kg of body weight per day or 600 mg per day.
      • Infants younger than 1 year of age—Dose is based on body weight and age and must be determined by your doctor.
    • For oral dosage form (extended-release capsules):
      • Adults, teenagers, and children 12 years of age and older weighing more than 45 kilograms (kg)—At first, 300 to 400 milligrams (mg) as a single dose, usually in the morning, or divided and given two times per day. Your doctor may adjust your dose as needed. However, the total dose is usually not more than 600 mg per day.
      • Older adults—The dose must be determined by your doctor. However, the total dose is usually not more than 400 milligrams per day as a single dose, usually in the morning, or divided and given two times per day.
      • Children and teenagers 12 to 15 years of age weighing less than 45 kilograms (kg)—Dose is based on body weight and must be determined by your doctor. At first, the dose is 12 to 14 milligrams (mg) per kg of body weight per day as a single dose, usually in the morning, or divided and given two times per day. Your doctor may adjust your dose as needed. However, the total dose is usually not more than 20 mg per kg of body weight per day or 600 mg per day.
      • Children younger than 12 years of age—Use and dose must be determined by your doctor.
    • For oral dosage form (extended-release tablets):
      • Adults, teenagers, and children 6 years of age and older weighing more than 45 kilograms (kg)—At first, 300 milligrams (mg) per day, divided and given every 12 hours. Your doctor may adjust your dose as needed. However, the total dose is usually not more than 600 mg per day.
      • Older adults—The dose must be determined by your doctor. However, the total dose is usually not more than 400 milligrams per day, divided and given every 12 hours.
      • Children and teenagers 6 to 15 years of age weighing less than 45 kilograms (kg)—Dose is based on body weight and must be determined by your doctor. At first, the dose is 12 to 14 milligrams (mg) per kg of body weight per day, divided and given every 12 hours. Your doctor may adjust your dose as needed. However, the total dose is usually not more than 20 mg per kg of body weight per day or 600 mg per day.
      • Children younger than 6 years of age—Use and dose must be determined by your doctor.

Modifications

A lower dose and frequent monitoring with Theo-24 may be required in certain circumstances:

  • People 65 years and older
  • Children
  • People with certain health conditions, such as congestive heart failure or liver impairment
  • A fever lasting for 24 hours or more

Smoking cigarettes can also affect how Theo-24 is absorbed in the body. Communicate with your healthcare provider about your smoking habits; if you quit smoking while on Theo-24, you may need a lower dose.

Talk to your healthcare provider if you are pregnant, plan to become pregnant, or are breastfeeding.

Missed Dose

If you miss a dose of Theo-24, take the next dose at the usual scheduled time. Do not take two doses together.

Overdose: What Happens If I Take Too Much Theo-24?

There are two types of overdoses with Theo-24:

  • An acute overdose can occur if you take too much Theo-24 at one time.
  • A chronic overdose can happen over time if your daily doses are too high.

A chronic overdose is more likely to cause problems, which can include seizures, life-threatening arrhythmias (irregular heartbeat), and death. If you have symptoms such as nausea or vomiting, do not take any more doses of Theo-24 until you contact your healthcare provider. You will need bloodwork to see how much theophylline is in your body.

What Happens If I Overdose on Theo-24?

If you think you or someone else may have overdosed on Theo-24, call a healthcare provider or the Poison Control Center (800-222-1222).

If someone collapses or isn't breathing after taking Theo-24, call 911 immediately.

Precautions

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It is very important that your doctor check the progress of you or your child at regular visits, especially for the first few weeks after you begin using this medicine. Blood tests may be needed to check for unwanted effects.

A change in your usual behavior or physical well-being may affect the way this medicine works in your body. Tell your doctor if you or your child:

  • Have had a fever of 102 degrees F or higher for at least 24 hours or more.
  • Have started or stopped smoking tobacco or marijuana in the last few weeks.
  • Have started or stopped taking another medicine in the last few weeks.
  • Have changed your diet in the last few weeks.

Stop using this medicine and check with your doctor right away if you or your child have the following symptoms while using this medicine: nausea or vomiting that continues, headaches, trouble with sleeping, seizures, or irregular heartbeats.

Do not stop or change the dose of this medicine without checking first with your doctor.

Before you have any medical tests, tell the medical doctor in charge that you or your child are using this medicine. The results of some tests may be affected by this medicine.

This medicine may add to the central nervous system (CNS) stimulant effects of caffeine-containing foods or beverages such as chocolate, cocoa, tea, coffee, and cola drinks. Avoid eating or drinking large amounts of these foods or beverages while using this medicine. If you have questions about this, check with your doctor.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems, and herbal (e.g., St. John's wort) or vitamin supplements.

What Are Reasons I Shouldn’t Take Theo-24?

Theo-24 is not appropriate for everyone. You should not take this medication if you are allergic to theophylline or any of the inactive ingredients in Theo-24.

Theo-24 may be prescribed with caution in some people but only if the healthcare provider determines it is safe. This includes neonates/infants, older adults (aged 65 and older), and people with these conditions:

What Other Medications Interact With Theo-24?

Theo-24 interacts with a wide variety of drugs. Review your current medication use, including prescription and over-the-counter (OTC), and vitamin and herbal supplement use with your healthcare provider.

Tell your provider before starting or stopping any other medication.

Some examples of drugs and substances that interact with Theo-24 include the following:

Other drug interactions may occur with Theo-24. Consult your healthcare provider for a complete list of drug interactions.

What Medications Are Similar?

Asthma or COPD treatment usually consists of several medications.

Similar to theophylline, aminophylline is a methylxanthine. However, it is available only in injectable form. It is used along with other medications to treat acute exacerbations of asthma or COPD.

Typically, theophylline is prescribed only when other therapies have failed or could not be tolerated. However, there are other oral medications prescribed to treat asthma. These drugs are categorized as leukotriene modifiers and include these medications:

People with asthma or COPD will also need a rescue, or fast-acting, inhaler, such as these:

Often, an inhaler is used daily to prevent symptoms. These may include the following:

  • An inhaled steroid such as Flovent HFA (fluticasone) or Alvesco (ciclesonide)
  • A combination long-acting beta-agonist (LABA) and inhaled steroid (a LABA must always be used with an inhaled steroid) such as Advair (fluticasone and salmeterol) or Symbicort (budesonide and formoterol)

In some cases, a person may not have adequate control of symptoms despite being treated with a combination of medications. A biologic may be prescribed, such as Xolair (omalizumab), which is an injection.

This list consists of examples of drugs also prescribed for asthma or COPD. It is NOT a list of drugs recommended to take with Theo-24.

Frequently Asked Questions

  • What is Theo-24 used for?

    Theo-24 is used on a daily basis to treat symptoms of asthma or COPD (including emphysema and chronic bronchitis). It does not treat acute attacks.

  • How does Theo-24 work?

    Theo-24 works by relaxing the smooth muscles of the airways to open air passages in the lungs, making it easier to breathe. It also relieves inflammation and suppresses the airway's response to stimuli like allergens.

  • What drugs should not be taken with Theo-24?

    Theo-24 interacts with a variety of medications and substances. Before taking Theo-24, tell your healthcare provider about all of the medications you take, including prescription and OTC drugs, vitamins, and herbal supplements. Certain antibiotics, anxiety medications, and seizure medications are examples of drugs that interact with Theo-24. Smoking cigarettes can also affect how Theo-24 is absorbed, so inform your healthcare provider if you quit smoking while on this medication.

  • How long does it take for Theo-24 to work?

    Theo-24 is an extended-release capsule. It is taken once every 24 hours as a preventive therapy; it does not treat acute attacks.

  • What are the side effects of Theo-24?

    The most common side effects of Theo-24 are stomach problems (e.g., nausea, vomiting, diarrhea), headache, trouble sleeping, feeling irritable or restless, tremors, and increased urination.

    Severe side effects can include seizures, irregular heartbeat, low blood pressure, and skin reactions.

    Get emergency medical help immediately if you have hives, difficulty breathing, or swelling around the face.

  • How do I stop taking Theo-24?

    Your healthcare provider will advise you on how long to take Theo-24. Do not stop taking the medication without medical guidance.

How Can I Stay Healthy While Taking Theo-24?

When taking Theo-24, follow your healthcare provider’s instructions for use. Read the patient information leaflet that comes with your prescription. Make sure to consult your healthcare provider any time you are sick with nausea, vomiting, or any type of new illness (especially if you have a fever). Let them know if you experience a persistent headache, trouble sleeping, or rapid heartbeat.

In addition to taking your medication as prescribed, here are other steps you can take to control your symptoms.

  • Avoid risk factors, such as smoking
  • Receive regular seasonal vaccinations, such as flu and pneumococcal infections
  • Exercise
  • Pulmonary rehabilitation and oxygen therapy, if needed

Many factors can affect your response to Theo-24, including whether you are taking other drugs. Habits like smoking can also reduce how much of the medication is absorbed in your body; therefore, a dosage adjustment may be necessary if you quit smoking. Before starting treatment, discuss with your healthcare provider your medical history and all medications you take.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended to replace medical advice, diagnosis, or treatment from a healthcare provider. Consult your healthcare provider before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Karen Berger, PharmD
Karen Berger, PharmD, is a community pharmacist and medical writer/reviewer.