Theo-24 SR (Theophylline) – Patient Information for Australia
Basic Product Information
| Active Ingredient (INN) | Theophylline |
|---|---|
| Australia Brand Names | Theo-24 SR, Nuelin SR, Theolair, (other generics may be available) |
| ATC Code | R03DA04 |
| Available Forms and Strengths | Modified-release tablets or capsules (typically 200 mg, 300 mg, 400 mg) |
| Manufacturers | Diverse international and Australian generic pharmaceutical companies |
| Prescription Status (Australia) | Prescription Only Medicine (Schedule 4) |
Mechanism of Action
Simple Explanation: Theophylline, the active ingredient in Theo-24 SR, helps relax and open the airways in your lungs, making it easier to breathe. It does this by relaxing the muscles around your air passages and reducing inflammation.
For Specialists: Theophylline is a methylxanthine bronchodilator. It inhibits phosphodiesterase, leading to increased cAMP levels in smooth muscle cells and subsequent smooth muscle relaxation. It also has mild anti-inflammatory effects, blocks adenosine receptors, and improves diaphragmatic contractility.
Pharmacokinetics (How Theo-24 SR Works in the Body)
- Absorption: After oral administration, Theo-24 SR is moderately to well absorbed, with modified-release formulations giving a steady theophylline level over 12–24 hours.
- Metabolism: Primarily metabolised by the liver (mainly CYP1A2 pathway).
- Elimination: The metabolites are excreted mainly via urine. Small fractions may be unchanged.
- Duration of Action: Modified-release formulas allow for once or twice daily dosing, maintaining stable blood levels for up to 24 hours.
- Special Notes: Liver or heart disease, certain foods, and other medications can affect theophylline levels.
Use in Everyday Life and Best Practices
Theo-24 SR is used as part of the long-term management of chronic asthma and chronic obstructive pulmonary disease (COPD). It is not usually the first medicine used. Rather, it’s prescribed when other treatments (such as inhaled corticosteroids or long-acting bronchodilators) are insufficient on their own.
- Typical adult starting dose: Usually 200–300 mg once daily, increased as needed, guided by blood theophylline levels.
- For children or elderly: Dose is adjusted according to age, weight, and clinic assessment.
- Regular use: Take at the same time each day to maintain an even level in your body.
- Do not use for sudden asthma attacks: Use your reliever inhaler for emergencies.
Dosing: Morning vs Evening
| Time of Day | Advantages | Disadvantages | Tips |
|---|---|---|---|
| Morning | May reduce risk of sleep disturbances (e.g., insomnia), easier to remember, aligns with meal times | Possible lower levels overnight in once-daily regimens | Preferred if sleep is affected |
| Evening | Higher levels overnight to cover morning symptoms | May cause insomnia, especially if sensitive to stimulants | Only use if well tolerated |
Advice: Whichever time is chosen, take Theo-24 SR at the same hour each day. If sleep difficulty arises, speak with your doctor or pharmacist about moving the dose earlier.
Taking Theo-24 SR With Food or on an Empty Stomach
- Theophylline absorption can be affected by food, but for modified-release formulations like Theo-24 SR, it is best to take with or just after food to reduce stomach upset.
- Consistent meal patterns (as per many Australian diets) help keep theophylline levels steady – avoid fasting or very high-fat meals as this may alter absorption.
Interaction Warnings
| Substance | Interaction | Advice |
|---|---|---|
| Coffee, tea, cola, chocolate | Contain caffeine, may increase stimulant side effects | Limit excessive intake |
| Alcohol | Can alter theophylline metabolism | Limit alcohol use, avoid binges |
| Macrolide antibiotics (e.g., erythromycin) | Increased theophylline blood levels | Doctor may reduce dose/monitor levels |
| Quinolone antibiotics (e.g., ciprofloxacin) | Can raise theophylline levels | Monitor for toxicity if co-prescribed |
| Carbamazepine, phenytoin, rifampicin | May lower theophylline levels | Doctor may adjust dose |
| St John’s Wort | Speeds up clearance, may reduce effect | Avoid use together |
| Heart/liver medicines (e.g., verapamil) | Possible theophylline increase | Monitor levels, adjust dose |
Indications
| Indication | Status | Notes |
|---|---|---|
| Chronic asthma (maintenance) | Approved | When other controller medication not sufficient |
| Stable COPD (maintenance) | Approved | Adjunct to inhaled therapies |
| Apnoea of prematurity | Off-label | Specialist use in hospitals |
| Other respiratory diseases (e.g. emphysema) | Occasionally used | Consult respiratory specialist |
Dosing According to Clinical Indications
| Population | Asthma/COPD Maintenance Dose | Max Daily Dose | Notes |
|---|---|---|---|
| Adults | 200–400 mg once or twice daily (adjusted by blood level monitoring) | 900 mg | Start low, monitor levels especially in elderly |
| Children (6–12 years) | 10–20 mg/kg/day, divided 2 daily | Usually up to 400 mg | Cautious titration, specialist guidance required |
| Elderly (>65 years) | Lower adult dose, monitor levels closely | As above | May need less due to slower metabolism |
| Renal/liver impairment | Individually adjusted based on blood levels | Lower than standard | Frequent monitoring |
Safety Profile and Side Effects
Most people tolerate Theo-24 SR well at the correct dose. Dose-related side effects are more likely if too much theophylline builds up in the body, so regular monitoring may be needed.
- Common:
- Nausea, vomiting, stomach pain
- Headache
- Insomnia (trouble sleeping)
- Restlessness, anxiety
- Increased need to urinate
- Rare but serious (call your doctor):
- Irregular heartbeat, palpitations
- Seizures (fits)
- Severe vomiting or persistent nausea
- Rash, especially with other symptoms
- Warnings:
- Tell your doctor about all your medicines, other conditions, and changes in smoking or diet.
- Theophylline has a narrow safety range: blood tests may be required to check your level, especially when starting, stopping, or adjusting your dose, or if you change other medicines.
Guidelines for Proper Use (Australia-Specific Tips)
- Follow your doctor’s instructions on dosing — do not alter your dose or stop suddenly without consulting your prescriber.
- Keep regular appointments for blood level monitoring if advised.
- Swallow tablets/capsules whole; do not crush or chew modified-release forms.
- Keep hydrated, especially in warmer Australian climates.
- Inform pharmacists and other healthcare professionals that you are taking theophylline, especially before starting new medications or herbal supplements.
- Avoid sudden changes in smoking habits as this can affect your theophylline dose needs.
- Report unexplained nausea, headaches, sleep changes, or palpitations to your healthcare team.
Alternative Treatment Options
- Inhaled corticosteroids (e.g., budesonide, fluticasone): Mainstay of asthma and COPD management; well tolerated; fewer systemic side effects than oral theophylline.
- Inhaled long-acting bronchodilators (e.g., salmeterol, formoterol, tiotropium): Convenient, targeted airway opening effects. Often preferred for both asthma and COPD.
- Leukotriene receptor antagonists (e.g., montelukast): Oral option for asthma, especially for those with allergic triggers.
- Oral corticosteroids: Short-term control in severe flare-ups, but not for long-term due to side effects.
- Pros/cons vs Theophylline: Theophylline is useful as an add-on when other options are not enough, but inhaled therapies are generally safer and preferred first-line due to fewer systemic effects.
- Most alternatives are covered by the Pharmaceutical Benefits Scheme (PBS) in Australia.
Legal, Registration, and Reimbursement Status in Australia
- Legal classification: Schedule 4 (Prescription Only Medicine) – cannot be purchased without a prescription from a registered Australian healthcare practitioner.
- Australian Register of Therapeutic Goods (ARTG): Registered and regulated by the Therapeutic Goods Administration (TGA).
- Available on PBS: Theophylline and slow-release theophylline products are reimbursed for eligible patients with asthma or COPD.
- Dispensing: Available at community and hospital pharmacies; certain criteria for subsidy apply (see your doctor for eligibility).
Latest Research and Clinical Guidance (2022–2025)
- Recent Australian guidelines (e.g., National Asthma Council Australia 2023, COPD-X Plan 2024) recommend theophylline only as an adjunct to inhaled therapies when other options are inadequate or not tolerated.
Sources: National Asthma Council Australia. Asthma Handbook, 2023. Lung Foundation Australia. COPD-X Concise Guide, 2024. - New formulations and improved slow-release mechanisms lower the risk of side effects, but close therapeutic monitoring remains essential.
- Multicentre trials (2023, UK/Australia/US) confirmed only modest improvement in symptom control; inhaled therapies are still preferred due to fewer adverse effects.
- Research into genetic differences in theophylline metabolism may allow individualised dosing in the future.
Availability and Delivery
| Pack Size | Strength | Indicative PBS Price (AUD)* | Available At |
|---|---|---|---|
| 60 tablets | 200 mg | $21–$29 | Community & Hospital Pharmacies |
| 100 capsules | 300 mg | $31–$40 | Community & Hospital Pharmacies |
| 60 tablets | 400 mg | $32–$41 | Pharmacy only (with prescription) |
*PBS co-payment for eligible patients may be considerably lower.
Indicative Delivery Times from Major Pharmacies
| City | Pick-up | Standard Delivery | Express Delivery |
|---|---|---|---|
| Sydney | Same day | 1–2 days | Next business day |
| Melbourne | Same day | 1–2 days | Next business day |
| Brisbane | Same day | 2–3 days | 1–2 days |
| Perth, Adelaide, Hobart | Same/next day | 3–4 days | 2 days |
Frequently Asked Questions (FAQ)
- 1. Can I drink coffee or tea while taking Theo-24 SR?
Yes, but limit amounts as caffeine can increase side effects of theophylline, such as jitteriness or palpitations. One or two cups daily are usually fine for most people. - 2. What should I do if I miss a dose?
Take your next dose at the usual time. Do not double-up to make up for a missed dose. If in doubt, ask your pharmacist or doctor. - 3. Is blood testing required while on Theo-24 SR?
Some patients may need regular blood tests to make sure the level of theophylline in their blood stays safe and effective, particularly when starting treatment or if other medicines are added. - 4. Can I crush Theo-24 SR tablets to make them easier to swallow?
No. Modified-release tablets must be swallowed whole to ensure the medicine is released slowly over time, otherwise there is a risk of toxicity or reduced effect. - 5. Can Theo-24 SR be used to treat an asthma attack?
No. This medicine is not suitable for sudden asthma symptoms. Always use your recommended reliever (such as salbutamol inhaler) for acute asthma attacks.
For any further questions about Theo-24 SR, consult your GP, pharmacist, or specialist respiratory healthcare team.
This information is up to date as of 2024 and follows the latest Australian recommendations. Always speak with your Australian healthcare provider about your specific circumstances and medication choices.
