The medication Durofilin (Theophylline) is generally used for the symptomatic relief and long-term management of breathing disorders.

It may be part of symptomatic management for conditions characterized by periods of heightened symptoms such as asthma and Chronic Obstructive Pulmonary Disease (COPD). It helps address symptoms like shortness of breath, chest tightness, wheezing, and persistent coughing.

In scenarios where additional symptomatic support is needed, Durofilin assists with managing symptoms that create noticeable functional strain. This supportive relief contributes to improved comfort and helps maintain a sense of stability when symptoms are more noticeable. It contributes to general well-being during symptomatic phases.

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Quick Fact: Relief for Breathing Difficulty

Durofilin is commonly used to help with acute or episodic breathing discomfort, providing support by easing the overall symptom burden and supporting the patient during difficult episodes by contributing to a sense of more stable breathing during challenging symptomatic phases.

Regulatory References

1. MedlinePlus Drug Information overview

Durofilin, which contains a combination of etofylline and theophylline, is typically prescribed for adults and children over 18 years old to manage symptoms of asthma, chronic bronchitis, and Chronic Obstructive Pulmonary Disease (COPD).

However, its use is contraindicated and should be avoided by patients with a known hypersensitivity or allergy to etofylline, theophylline, or any other xanthine derivatives. This medication is also not recommended for individuals with certain pre-existing conditions:

• Active Peptic Ulcer Disease: The drug may worsen existing stomach ulcers.
• Severe Hepatic or Renal Impairment: Liver and kidney problems can slow down the clearance of the medicine, increasing the risk of toxicity.
• Seizure Disorders (e.g., Epilepsy) or a history of seizures.
• Serious Heart Conditions such as acute myocardial infarction or certain tachyarrhythmias (rapid, irregular heart rhythms).

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Caution is Advised

Close medical supervision and potential dose adjustment are necessary for patients with congestive heart failure, hypothyroidism, hyperthyroidism, existing cardiovascular disease, or those who smoke. Special caution is also used for the elderly due to slower drug metabolism and in children under 18 years, where use is generally limited unless prescribed by a specialist.

The official interaction profile for Durofilin (Choline Theophyllinate) details specific combinations that are restricted based on regulatory documentation. Certain drug-drug combinations are formally classified as contraindicated or should usually be avoided, including co-administration with Fluvoxamine and the anesthetic agent Ketamine/Esketamine, due to the potential for significantly altered concentrations or severe adverse effects such as lowering the convulsive threshold.

Many documented interactions involve substances that modify theophylline’s metabolic clearance. Co-administration with strong enzyme inhibitors, such as the antibiotic Ciprofloxacin, Cimetidine, or Allopurinol, is documented to increase theophylline plasma concentrations, a pharmacokinetic effect that can lead to increased exposure. Conversely, enzyme inducers like Rifampicin, Phenytoin, and the herbal product St John’s Wort are officially noted to increase theophylline clearance, which reduces systemic exposure.

Pharmacodynamic interactions are also documented, such as use with Beta-Adrenergic Agonists (e.g., Salbutamol), which can potentiate effects and increase the risk of hypokalaemia. Furthermore, regulatory documents cite that lifestyle factors like smoking and physiological states, such as established hepatic impairment, significantly alter the drug’s clearance rate, with clearance being decreased by fifty percent or more in the latter population.

A1 Receptor Modulation

Durofilin acts as a modulator of the A1 receptor (Adenosine A1 Receptor), which is involved in various cellular inflammatory signaling pathways. This action alters the signaling cascade downstream of the A1 receptor, influencing general cellular activity and biochemical signaling.

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PDE4 Enzyme Inhibition

The compound also exerts its effect by inhibiting the PDE4 enzyme (Phosphodiesterase 4). PDE4 is responsible for the breakdown of cyclic AMP (cAMP), a crucial intracellular second messenger. By inhibiting PDE4, Durofilin alters the intracellular concentration of cAMP, effectively increasing its availability within the cell.

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Modulation of Bone Metabolism

The resultant changes in cAMP levels and the combined A1 receptor modulation influence multiple cellular functions. Specifically, these mechanistic changes modulate the activity of osteoclasts and other cellular components involved in the dynamic process of bone metabolism. This dual pathway modulation is a key factor in the overall pharmacological effect.

How to Use Durofilin (Theophylline Extended-Release)

Durofilin is an oral medication containing the active ingredient theophylline, typically in an extended-release capsule or tablet formulation for oral administration. It is essential to follow the specific instructions provided by your healthcare professional and those on the official prescription label, as the dose and frequency are highly individualized.

Official Administration Guidelines

Administration Scope	General Guidelines (based on Theophylline ER)
Route of Administration	Oral
Dosing Schedule	Dosing intervals are typically 12-hour for most patients, or 24-hour for select patients, to maintain a constant amount in the blood. The exact dose (e.g., 300 mg) is determined by the prescriber based on weight, age, and individual response.
Procedural Steps	Swallow the extended-release capsule or tablet whole; do not crush, cut, or chew it. For certain extended-release capsules, the contents may be sprinkled over a small amount of applesauce.
Timing in Relation to Meals	Extended-release capsules are best taken one hour before a high-fat meal or without food. Extended-release tablets may be taken with or without food. Always aim to take the medicine at the same time each day.
Missed-Dose Rules	If a dose is missed, skip it and take the next dose at the normal scheduled time. Do not take extra medicine or two doses at once to make up for a missed dose.

Age-Specific Use Considerations

The clearance of theophylline varies significantly with age. Pediatric and geriatric patients require careful attention to dose selection and frequent monitoring of blood theophylline concentrations due to differences in metabolism and clearance. The dose for infants and children under 16 years of age is specifically determined by body weight and requires close medical supervision.

Evidence for Use in Chronic Obstructive Pulmonary Disease (COPD)

Research primarily focused on managing COPD using Randomized Controlled Trials (RCTs) and observational cohort studies. Studies examined functional measures (e.g., FEV1), symptom scores, and the frequency of severe exacerbations. Studies monitored how airflow measurement shifted over defined time intervals. However, research examining outcomes related to the rate of COPD exacerbations, particularly when used as an add-on therapy to existing inhaled medicines, has yielded mixed findings across different trials.

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Evidence for Use in Chronic Asthma and Airflow Obstruction

Durofilin was studied for its use in chronic asthma and reversible obstruction. The initial evidence base comes from RCTs and comparative studies that examined physiological outcomes related to airflow changes, monitoring functional outcomes like peak expiratory flow ( PEFR). Research describes how airflow measurement shifts were monitored. More recent studies evaluated the compound in acute care settings, but findings demonstrated heterogeneity in the reported outcomes, reflecting varying patient severity and treatment combinations.

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Long-Term Studies and Observation Periods

The evidence base includes various types of studies with differing follow-up durations, ranging from short-term observation to intermediate periods (up to one year) for exacerbation endpoints. To understand long-term events, researchers relied heavily on observational cohort studies monitoring patient groups over multiple years, allowing data to show patterns related to all-cause mortality. These findings describe group patterns, not personal outcomes, and do not establish direct causality.

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Research in Special and Subgroup Populations

Durofilin was evaluated in specific patient populations, including studies focused on adults with varying disease severity and pediatric cohorts. Data for certain groups, such as those with specific comorbidities, remain insufficient. Research has not fully established the specific serum concentration associated with the outcomes measured in pediatric studies.

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Key Research Gaps and Areas of Uncertainty

A significant limitation is that much of the foundational evidence was conducted many years ago and precedes the use of other inhaled therapies. Consequently, comparative evidence is lacking in the form of large, contemporary trials. Findings remain mixed regarding the compound's effect on reducing COPD exacerbation frequency. The evidence quality varies across studies, and many areas of long-term observation and contemporary comparative use are not fully established.

Key Studies & References Chronic Use of Theophylline and Mortality in Chronic Obstructive Pulmonary Disease: A Meta-analysis

Common questions about Durofilin (FAQ)

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Q: What is the active ingredient in Durofilin?

Durofilin contains the active substance theophylline. According to the official product information, theophylline belongs to a group of medicines called xanthine derivatives.

Q: What is Durofilin prescribed for?

Regulatory documents state that Durofilin is prescribed for the prevention and treatment of conditions involving narrowed airways, such as bronchial asthma and chronic obstructive pulmonary disease (COPD). Its action, as described in regulatory documents, involves relaxing the muscles around the airways to help ease breathing.

Q: Can I take Durofilin if I have a stomach ulcer?

According to the official product information, peptic ulcer disease is listed as a condition where Durofilin should not be used. For this reason, the use of Durofilin is generally listed as contraindicated in the presence of active peptic ulcer disease, according to the official product label.

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

Official product information contains instructions stating that if a dose is missed, patients are typically advised to skip the missed dose and resume the normal dosing schedule. It is also specified that taking a double dose to compensate for a missed one is generally cautioned against in the instructions.

Q: Can Durofilin be taken with food?

Studies and official information indicate that Durofilin tablets are typically taken after meals with a glass of water. Regulatory documents mention taking the medicine after meals with water as the standard administration instruction.

Q: How should Durofilin tablets be taken (swallowed)?

According to the official product information, Durofilin tablets must be swallowed whole. The regulatory documents explicitly state that the tablets must not be broken, crushed, or chewed before swallowing.

Durofilin (Choline Theophyllinate) must be stored strictly according to the conditions defined in the official regulatory labeling for its active component.

Official Storage Conditions

The medicine requires storage at Controlled Room Temperature, which is defined as 20 C to 25 C (68 F to 77 F). The product may be exposed to brief temperature excursions up to 30 C (86 F). The container must be kept tightly closed and in a cool, dry place to protect the product from moisture.

Child-Safety Storage

The product must be stored out of the reach of children.

Disposal Instructions

Unused or expired Durofilin should be discarded using an authorized drug take-back program. If no program is available, the product must be mixed with an undesirable substance, sealed in a container, and placed in the household trash. The drug must not be flushed down a sink or toilet unless explicitly instructed by the product labeling.