Theo-Dur (Oral)
Generic name: theophylline [ thee-OF-i-lin ]
Brand names: Elixophyllin, Norphyl, Phyllocontin, Quibron-T, Quibron-T/SR,
... show all 12 brands
Drug class: Methylxanthines
Medically reviewed by Drugs.com. Last updated on Aug 25, 2024.
The Theo-Dur brand name has been discontinued in the U.S. If generic versions of this product have been approved by the FDA, there may be generic equivalents available.
See also: Theo-24
Uses for Theo-Dur
Theophylline is used together with other medicines to treat the symptoms of asthma, bronchitis, emphysema, and other lung diseases.
Theophylline belongs to a group of medicines known as bronchodilators. Bronchodilators are medicines that relax the muscles in the bronchial tubes (air passages) of the lungs. They relieve cough, wheezing, shortness of breath, and troubled breathing by increasing the flow of air through the bronchial tubes.
This medicine is available only with your doctor's prescription.
Before using Theo-Dur
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Allergies
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Pediatric
Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of theophylline in children. However, children younger than 1 year of age are more likely to have serious side effects, which may require caution and an adjustment in the dose for patients receiving theophylline.
Geriatric
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of theophylline in the elderly. However, elderly patients may be more sensitive to the effects of theophylline than younger adults, and are more likely to have kidney, liver, heart, or lung problems, which may require caution and an adjustment in the dose for patients receiving theophylline.
Breast Feeding
Studies in women suggest that this medication poses minimal risk to the infant when used during breastfeeding.
Interactions with Medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
- Riociguat
- Viloxazine
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Abametapir
- Adalimumab
- Adenosine
- Amifampridine
- Bupropion
- Capmatinib
- Ceritinib
- Cimetidine
- Ciprofloxacin
- Deferasirox
- Desogestrel
- Dienogest
- Dihydroartemisinin
- Donepezil
- Drospirenone
- Enoxacin
- Erythromycin
- Estetrol
- Estradiol
- Ethinyl Estradiol
- Ethynodiol
- Etintidine
- Etonogestrel
- Febuxostat
- Fluconazole
- Fluvoxamine
- Fosphenytoin
- Gestodene
- Givosiran
- Halothane
- Idrocilamide
- Imipenem
- Ketamine
- Leniolisib
- Levofloxacin
- Levonorgestrel
- Medroxyprogesterone
- Mestranol
- Methacholine
- Mexiletine
- Nomegestrol
- Norelgestromin
- Norethindrone
- Norgestimate
- Norgestrel
- Paroxetine
- Pefloxacin
- Peginterferon Alfa-2a
- Peginterferon Alfa-2b
- Phenytoin
- Pixantrone
- Regadenoson
- Ritlecitinib
- Rofecoxib
- Segesterone
- Taurursodiol
- Thiabendazole
- Tocilizumab
- Troleandomycin
- Vemurafenib
- Zileuton
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Adinazolam
- Alprazolam
- Aminoglutethimide
- Amiodarone
- Azithromycin
- Bentazepam
- Bromazepam
- Brotizolam
- Carbamazepine
- Chlordiazepoxide
- Clobazam
- Clonazepam
- Clorazepate
- Delorazepam
- Diazepam
- Disulfiram
- Estazolam
- Flunitrazepam
- Flurazepam
- Halazepam
- Interferon Alfa-2a
- Ipriflavone
- Isoproterenol
- Ketazolam
- Loprazolam
- Lorazepam
- Lormetazepam
- Medazepam
- Metaclazepam
- Methotrexate
- Midazolam
- Nilutamide
- Nitrazepam
- Oxazepam
- Pancuronium
- Pentoxifylline
- Phenobarbital
- Pinazepam
- Piperine
- Prazepam
- Propafenone
- Quazepam
- Remimazolam
- Rifampin
- Rifapentine
- Ritonavir
- Secobarbital
- Semaglutide
- St John's Wort
- Tacrine
- Telithromycin
- Temazepam
- Tetrazepam
- Ticlopidine
- Triazolam
- Zafirlukast
Interactions with Food/Tobacco/Alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following is usually not recommended, but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.
- Tobacco
Using this medicine with any of the following may cause an increased risk of certain side effects but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.
- Caffeine
- food
Other Medical Problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Congestive heart failure or
- Cor pulmonale (heart condition) or
- Fever of 102 degrees F or higher for 24 hours or more or
- Hypothyroidism (underactive thyroid) or
- Infection, severe (e.g., sepsis) or
- Kidney disease in infants younger than 3 months of age or
- Liver disease (e.g., cirrhosis, hepatitis) or
- Pulmonary edema (lung condition) or
- Shock (serious condition with very little blood flow in the body)—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
- Heart rhythm problems (e.g., arrhythmia) or
- Seizures, or history of or
- Stomach ulcer—Use with caution. May make these conditions worse.
Proper use of Theo-Dur
Take this medicine exactly as directed by your doctor. Do not take more of it and do not take it more often than your doctor ordered. This medicine works best if there is a constant amount in the blood. To keep the blood level constant, take this medicine at the same time each day and do not miss any doses.
After you or your child begin taking theophylline, it is very important that your doctor check the level of the medicine in the blood at regular intervals to decide if the dose needs to be changed. Keep all appointments for testing the blood level.
Take the extended-release capsule or tablet every morning at the same time each day. You may take your second dose 10 to 12 hours after the morning dose and before the evening meal, unless your doctor tells you otherwise.
Swallow the extended-release tablet whole. Do not break, crush, or chew it. You may take the extended-release tablet with or without food.
It is best to take the extended-release capsule one hour before a high-fat meal or without food.
Measure the oral liquid with a marked measuring spoon, oral syringe, or medicine cup. The average household teaspoon may not hold the right amount of liquid.
Dosing
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.
- For oral dosage form (elixir or tablets):
Missed Dose
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Storage
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
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Precautions while using Theo-Dur
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.
Side Effects of Theo-Dur
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Incidence not known
- Chest pain or discomfort
- dizziness
- fainting
- fast, slow, or irregular heartbeat
- increase in urine volume
- lightheadedness
- persistent vomiting
- pounding or rapid pulse
- seizures
- shakiness
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
- Abdominal or stomach pain
- blurred vision
- confusion
- confusion about identity, place, and time
- dark-colored urine
- decrease in frequency of urination
- decreased urine
- diarrhea
- difficulty in passing urine (dribbling)
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
- dry mouth
- fast, pounding, or irregular heartbeat or pulse
- fever
- increased thirst
- irregular heartbeat
- loss of appetite
- mood changes
- muscle cramps or spasms
- muscle pain or stiffness
- nausea or vomiting
- nervousness
- numbness or tingling in the hands, feet, or lips
- pain or discomfort in the arms, jaw, back, or neck
- painful urination
- shakiness in the legs, arms, hands, or feet
- shortness of breath
- sweating
- unusual tiredness or weakness
- vomiting of blood or material that looks like coffee grounds
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Incidence not known
- Headache
- irritability
- restlessness
- sleeplessness
- trouble sleeping
- unable to sleep
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Commonly used brand name(s)
In the U.S.
- Elixophyllin
- Norphyl
- Phyllocontin
- Quibron-T
- Quibron-T/SR
- Theo-24
- TheoCap
- Theochron
- Theo-Dur
- Theo-Time
- Truxophyllin
- Uniphyl
Available Dosage Forms:
- Tablet, Extended Release
- Tablet, Extended Release, 12 HR
- Capsule, Extended Release, 24 HR
- Solution
- Elixir
- Tablet, Extended Release, 24 HR
Therapeutic Class: Bronchodilator
Chemical Class: Methylxanthine
More about Theo-Dur (theophylline)
- Check interactions
- Compare alternatives
- Drug images
- Side effects
- Dosage information
- During pregnancy
- Drug class: methylxanthines
- Breastfeeding
Patient resources
Other brands
Theo-24, TheoCap, Theochron, Uniphyl, ... +5 more
Professional resources
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Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.