Theo-24 Sr (Theophylline) – Patient Guide (Australia)

Theo-24 Sr contains theophylline, a medicine used to help open airways and improve breathing in certain long-term lung conditions. This guide explains what Theo-24 Sr is, how it works, how to take it safely, what to expect, and important interactions and safety information.

Always follow the instructions provided with your medicine. If you have questions or concerns, speak with a pharmacist or doctor.

Basic product information

• Modified-release (SR) means the medicine is released slowly over time.
• Theo-24 Sr is typically used when longer-lasting blood levels are desired (rather than frequent dosing throughout the day).

What is theophylline and how does Theo-24 Sr work?

Mechanism of action

Theophylline is a methylxanthine bronchodilator. It helps improve breathing primarily by:

• Relaxing airway smooth muscle, making the airways less tight.
• Improving airway calibre (the size of airways), which can reduce shortness of breath and wheeze.
• Modulating inflammation and airway responsiveness, which may contribute to symptom control.

The result is often fewer symptoms during the day and night for suitable people with chronic, reversible airway disease.

Pharmacokinetics (how the body handles it)

Understanding pharmacokinetics can help explain why timing and interactions matter. Theophylline absorption and clearance can vary between people, and blood levels can be affected by other medicines and lifestyle factors.

• Absorption: Theo-24 Sr is designed to release theophylline gradually. Taking it with food may affect absorption for some people, but the formulation is intended to support stable levels.
• Distribution: Theophylline distributes throughout body tissues. It is important to maintain safe therapeutic levels because the medicine has a relatively narrow margin between effective and potentially harmful doses.
• Metabolism: Mostly metabolised by the liver (primarily via enzymes such as CYP1A2).
• Excretion: Metabolites are excreted primarily by the kidneys.
• Half-life: Can vary substantially depending on age, liver function, smoking status, and interacting medicines.

Because theophylline levels can be affected by many factors, clinicians may use blood level monitoring in some situations (for example, if symptoms persist, dosing changes, side effects occur, or interactions are present).

Typical use and indications

Indications (what Theo-24 Sr is used for)

Theophylline is used as an add-on treatment for certain chronic lung conditions where symptoms can improve with bronchodilation. In practice, it may be considered for people with:

• Chronic obstructive pulmonary disease (COPD) in selected patients
• Asthma in selected situations, particularly where control is inadequate with standard therapy
• Reversible airway disease where long-term bronchodilation is needed

Your clinician will determine whether Theo-24 Sr suits you based on your diagnosis, symptom pattern, other medicines, and your risk factors for side effects.

When does it start working? Timing and dosing schedule

Onset and duration

• Modified-release formulations aim for symptom relief over an extended period.
• Some improvement may be noticed after the dose is established, but the full benefit is usually judged over days to weeks.

Typical timing

A common approach is once or twice daily dosing depending on the specific strength and your prescribed regimen. Because Theo-24 Sr is sustained release, it is usually taken at consistent times each day.

• Try to take it at the same time(s) daily.
• Use your pharmacy label to follow the exact schedule.
• If you miss a dose, refer to the “What to do if you miss a dose” section below.

Dosing (general guidance)

Dosing of theophylline is individual. It often depends on age, lung condition, liver and kidney function, smoking status, and concurrent medicines. Because toxicity can occur at higher levels, the safest dose for you is the one your clinician prescribes.

Key points about dose selection

• Start low and adjust carefully: Many people require gradual titration to reach effective and safe levels.
• Blood level monitoring may be used: Especially when starting, changing dose, or when interacting medicines are introduced.
• Smoking affects metabolism: Smoking can lower theophylline levels, while stopping smoking can increase levels.

How to take Theo-24 Sr

• Swallow whole and do not crush or chew the modified-release formulation unless the product instructions specifically allow it.
• Take with water.
• If you experience stomach upset, discuss with a pharmacist—timing with meals may help in some people.

Note: Specific tablet strength and regimen can vary. Always follow the dosing directions on your prescription label and product information.

Food interactions

General guidance with meals

Food can influence absorption of medicines. For Theo-24 Sr, the most important practical approach is consistency:

• Take each dose the same way each day (either always with food or always on an empty stomach), unless your clinician advises otherwise.
• If your healthcare professional has recommended taking it with meals, follow that advice.

Caffeine and similar stimulants

Theophylline is a stimulant-like medicine. Avoid or limit excessive caffeine (for example, frequent energy drinks, very strong coffee) because it may increase side effects such as palpitations, anxiety, tremor, or insomnia.

Alcohol interactions

Alcohol can affect theophylline metabolism and may increase the risk of side effects (such as nausea, stomach upset, dizziness, or sleep disturbance). It may also worsen underlying symptoms or trigger reflux in some people, which can aggravate breathlessness.

• Limit or avoid alcohol unless your clinician confirms it is safe for you.
• If you drink alcohol, be alert for symptoms of intolerance (e.g., fast heartbeat, vomiting, severe headache, unusual agitation).

Medicine interactions (important)

Theophylline has many potential interactions because it is metabolised in the liver and can affect the handling of other medicines. Interaction risk is a major reason why blood levels may be monitored for some people.

Common categories of interacting medicines

• Antibiotics (some may increase theophylline levels)
• Medicines for fungal infections (may increase theophylline levels)
• Medicines for epilepsy/seizures (may lower theophylline levels)
• Medicines for smoking cessation effects can be complex; stopping smoking can raise levels
• Cimetidine (may increase theophylline levels)
• Rifampicin and some other enzyme inducers (may lower levels)
• Some heart rhythm medicines and other drugs that affect heart rate

Stimulants and other bronchodilators

• Other beta-agonists and respiratory medicines may be used together, but side effects (like fast heart rate) can be more likely if combined with theophylline.
• Tell your clinician if you are using frequent “reliever” inhalers or if you have new palpitations.

Always check before starting

Before you begin any new medicine (including herbal products and over-the-counter products), ask your pharmacist to check for interactions with theophylline.

Safety profile: side effects and when to seek help

Common side effects

Side effects often relate to the stimulant effects of theophylline or to higher-than-expected blood levels.

• Nausea, vomiting
• Heartburn, stomach discomfort
• Headache
• Restlessness or nervousness
• Tremor
• Insomnia
• Fast heartbeat (palpitations)

Serious side effects (urgent medical attention)

Seek urgent medical help if you develop signs that suggest theophylline toxicity or serious heart rhythm problems, such as:

• Severe or persistent vomiting
• Uncontrolled shaking, severe agitation, confusion
• Fainting, severe dizziness
• Chest pain
• Very fast or irregular heartbeat
• Seizures

Who is at higher risk of toxicity?

• Older adults
• People with liver impairment
• People with heart rhythm problems
• Those who start or stop smoking
• Those taking interacting medications
• People with certain infections or fever (which can affect metabolism)

Practical use tips (to get the best and safest results)

• Consistency is key: Keep dosing times consistent every day.
• Avoid crushing/chewing SR: Modified-release should remain intact to release correctly.
• Track symptoms: Record wheeze, shortness of breath, nighttime symptoms, and how often you need a reliever inhaler.
• Monitor caffeine intake: Keep stimulants steady; avoid energy drinks.
• Tell your healthcare team about smoking changes: Start/stop smoking can change levels.
• Be cautious with fever and acute illness: Some illnesses can increase theophylline levels—seek advice if you feel unwell.
• Keep follow-up appointments: If blood level monitoring is planned, attend as recommended.

What to do if you miss a dose

If you miss a dose, follow these general principles:

• If you remember soon after: take it if it is still close to the scheduled time.
• If it is almost time for your next dose: skip the missed dose.
• Do not double up to make up for a missed dose.

For the exact approach, refer to the instructions on your product pack or your pharmacist’s advice.

Withdrawal and stopping Theo-24 Sr

Do not stop theophylline suddenly without medical advice. Stopping may worsen breathing symptoms in some people. If you need to stop, your clinician will advise a safe plan.

Alternative options

Treatment for asthma and COPD has many options. Depending on your condition and severity, alternatives may include:

For asthma

• Inhaled corticosteroids (ICS) (with or without long-acting bronchodilators)
• Long-acting beta-agonists (LABA) in combination products
• Leukotriene receptor antagonists (selected patients)
• Biologic medicines for specific asthma phenotypes (specialist care)

For COPD

• Long-acting bronchodilators (LAMA/LABA combinations)
• Inhaled corticosteroids for selected patients
• Other add-on therapies depending on symptoms and exacerbation history

Your healthcare provider can explain why Theo-24 Sr may be chosen for you, or why an alternative might be safer or more effective.

Market and legal context in Australia (general information)

In Australia, medicine availability is governed by the Australian Regulatory framework and medicine scheduling under the Poisons Standard. Many respiratory medicines are supplied through pharmacies and may be categorised differently depending on strength and formulation.

Online pharmacies in Australia typically verify that orders comply with relevant requirements and that you receive correct product information. If you are unsure about eligibility or the correct product for your needs, contact a pharmacist.

Product availability can change over time due to supply, manufacturer decisions, or regulatory updates.

Recent guidance and monitoring considerations

Ongoing clinical guidance for asthma and COPD emphasises:

• Using inhaled therapies as foundational treatment (particularly ICS-containing regimens for asthma).
• Careful review of the need for add-on oral medicines.
• For theophylline specifically, attention to drug interactions and individual dosing due to variable clearance and potential toxicity.
• Considering blood level monitoring when risk is higher or when making dose adjustments.

Guidance can be updated as new evidence emerges. If you have questions about whether Theo-24 Sr remains appropriate for you, ask your treating clinician.

Delivery, availability, and what to expect when ordering online

If you order Theo-24 Sr online through an Australian pharmacy, you can generally expect:

• Product verification: The correct form and strength for your needs.
• Pharmacist support: Access to advice about dosing, interactions, and side effects.
• Delivery options: Delivery times vary by location and courier service.

Stock levels may fluctuate. During high-demand periods, delivery may take longer. Check the website’s delivery estimate at checkout and allow extra time for rural/remote areas.

Frequently Asked Questions (FAQ)

1) How long can I take Theo-24 Sr?

Many people use theophylline as a long-term controller option if it suits their condition and tolerability. The duration should be reviewed regularly by your healthcare provider, particularly if symptoms improve or if side effects occur.

2) Will Theo-24 Sr replace my inhaler?

Usually not. Theo-24 Sr is typically an add-on therapy. Your reliever inhaler and/or preventer inhaler are usually continued as directed. If you find you need your reliever more often, contact your clinician promptly.

3) Can I take Theo-24 Sr with my other medicines for asthma/COPD?

Often, yes—but not always. Interactions depend on what you take. Tell your pharmacist about all medicines (including over-the-counter and herbal products) so they can check safety.

4) Is Theo-24 Sr safe for older adults?

Older adults may be more sensitive to theophylline due to slower clearance and higher side-effect risk. Lower starting doses and close monitoring may be needed. Discuss your personal risk with your clinician.

5) What should I do if I get palpitations or feel shaky?

Stop and seek medical advice promptly, especially if symptoms are severe or persistent. Palpitations, tremor, and agitation can be signs of too much theophylline or a heart rhythm issue.

6) Do I need blood tests?

Some people need blood level testing, particularly during initiation, dose changes, suspected toxicity, or when interacting medicines are started. Your clinician will decide based on your situation.

7) Does smoking affect Theo-24 Sr?

Yes. Smoking can change theophylline metabolism. Starting or stopping smoking can alter the level and side-effect risk. Let your healthcare provider know about any changes.

8) Can I drink coffee or energy drinks?

Limit caffeine and avoid energy drinks. Large or sudden changes in caffeine intake can increase the likelihood of side effects such as anxiety, tremor, or palpitations.

9) What if I’m taking antibiotics or antifungal medicines?

Some antibiotics and antifungal medicines can increase theophylline levels. Ask your pharmacist to check interactions before you start them, and contact your clinician if you feel unwell after starting.

10) What if Theo-24 Sr doesn’t seem to work?

Don’t adjust the dose on your own. Discuss with your clinician—there may be absorption issues, interactions, the need for blood level checking, or the need to review your overall asthma/COPD plan.

Summary

Theo-24 Sr (theophylline) is a modified-release bronchodilator used to help improve airflow and reduce symptoms in selected people with asthma/COPD or reversible airway disease. It can be effective, but safe use depends on careful dosing, awareness of interactions (including many commonly used medicines), and attention to side effects.

If you are starting Theo-24 Sr or changing your dose, consider regular review with your pharmacist or clinician—especially if you have other medical conditions, take multiple medicines, or smoke.