Theo-24 Sr (Theophylline) – Patient Information (UK)

Theo-24 Sr contains theophylline, a medicine used to help control symptoms in certain breathing conditions. This guide is written to be patient-friendly and to explain how the medicine works, how it is typically used in the UK, and what to consider for safety.

Basic product information

Theo-24 Sr is a sustained-release formulation of theophylline. Sustained release means the medicine is released slowly over time, helping to maintain levels in your blood for longer. This may improve symptom control compared with faster-release preparations.

In the UK, theophylline is generally used when appropriate for long-term symptom control, particularly where other treatments alone are not enough or are unsuitable. Your prescriber and pharmacist can confirm whether Theo-24 Sr is the most suitable option for you.

How Theo-24 Sr works (mechanism of action)

Theophylline helps the airways in several ways. It is thought to work mainly by:

• Relaxing airway smooth muscle – helping to reduce tightness and improve airflow.
• Reducing bronchoconstriction – decreasing the tendency for airways to narrow.
• Anti-inflammatory effects – contributing to fewer symptoms over time for some people.
• Modulating respiratory responses – which may reduce symptoms triggered by irritation or airway inflammation.

Because it is sustained release, Theo-24 Sr aims to provide steadier theophylline levels, rather than high peaks followed by low troughs.

Pharmacokinetics (how the body handles it)

Understanding pharmacokinetics can explain why timing, food, smoking status, and interacting medicines matter.

Absorption

• Theophylline is absorbed from the gut, and sustained release preparations are designed to release the drug gradually.
• Absorption can vary between individuals, so blood levels (where monitored) may be used to guide dosing.

Distribution

• Theophylline distributes throughout body tissues and crosses the blood–brain barrier.
• It can bind to blood proteins, which may affect how it behaves in the body.

Metabolism and elimination

• Theophylline is primarily metabolised by the liver.
• How quickly the body clears the drug can change with age, liver function, other medicines, and smoking.
• The medicine is eventually eliminated mainly via the kidneys.

Why monitoring may be considered: Theophylline can have a relatively narrow range between beneficial and harmful effects. That’s why clinicians sometimes check blood theophylline levels, especially when starting, adjusting dose, or if interactions occur.

What it’s used for (typical use and indications)

Theophylline is used as an add-on maintenance therapy for certain chronic respiratory conditions. In the UK, it is most commonly associated with:

• Chronic Obstructive Pulmonary Disease (COPD) – to help control breathlessness and wheeze in selected patients.
• Asthma (in some circumstances) – particularly for people who do not achieve adequate control with standard inhaled therapies.

Whether Theo-24 Sr is appropriate for you depends on your symptoms, lung function, current treatments (especially inhalers), and your risk factors for side effects or interactions.

When and how to take Theo-24 Sr (timing)

Because Theo-24 Sr is sustained release, it is usually taken in a way that provides steady coverage. Always follow the instructions provided by your healthcare professional and the product label.

General timing guidance

• Try to take it at the same time each day to keep levels steadier.
• If it’s prescribed once daily, it’s often taken in the evening; if twice daily, spacing is important.
• Do not double up to make up for a missed dose unless advised.

How to swallow

• Swallow the tablet/capsule whole as directed.
• Do not crush or chew sustained-release forms unless your pharmacist confirms it is safe for your specific product.

Dosing (typical approach)

Dosing of theophylline is individualised because blood levels and side-effect risk vary significantly. Factors include age, liver function, smoking status, and interacting medicines.

Your clinician will select a starting dose and then adjust as needed. In some cases, blood tests may be used to confirm that levels are in a safer, effective range.

Practical dosing principles

• Start low in people at higher risk of side effects.
• Increase gradually if needed, depending on response and tolerability.
• Seek advice if you miss doses or if your dose schedule changes due to illness.

Important: Do not change the dose or schedule without medical advice. Theophylline-related side effects can occur when levels become too high.

Food interactions

Food can influence theophylline absorption and how quickly levels rise. The most important food-related issues include consistency and avoiding large, sudden changes.

• Taking with or without food may affect absorption for some people. Follow the way you were instructed to take it (for example, “with food” or “on an empty stomach”).
• If you notice symptoms such as nausea, tremor, palpitations, or sleep disruption after a particular food pattern, discuss it with your pharmacist/clinician.
• Alcohol-containing drinks and some dietary supplements may also interact (see alcohol section below).

If you are unsure whether to take Theo-24 Sr with food, ask your pharmacist.

Alcohol interactions

Alcohol may increase side effects and can affect liver metabolism. The combination may make it harder to predict theophylline levels and tolerability.

• It’s generally safest to keep alcohol intake moderate and avoid binge drinking.
• If you drink alcohol regularly, tell your pharmacist—your dose may need review.
• Avoid alcohol if you have previously had theophylline side effects or symptoms of high levels.

If you develop symptoms such as severe vomiting, rapid heartbeat, shaking, or confusion, seek urgent medical help.

Medicine interactions (important)

Theophylline interacts with a number of commonly used medicines, and these interactions can either raise theophylline levels (increasing the risk of side effects) or lower levels (reducing effectiveness).

Tell your pharmacist/clinician about all medicines you take, including:

• prescription medicines
• over-the-counter products (including cold/flu remedies)
• herbal products and supplements
• nicotine replacement products

Examples of medicines that may interact

This is not an exhaustive list. Your healthcare professional can check specific interactions for your medicines.

• Antibiotics (some types can raise theophylline levels).
• Fluoroquinolone antibiotics and certain other antimicrobial medicines may require special caution.
• Antifungal medicines (can affect metabolism of theophylline).
• Rifampicin (may lower theophylline levels).
• Epilepsy medicines (some can alter theophylline clearance).
• Certain heart rhythm or cardiovascular medicines (may affect heart rate or rhythm and the overall risk profile).
• Cimetidine (can raise theophylline levels).
• Some antidepressants and other central nervous system medicines may affect risk.

Smoking (a major interaction)

Smoking can lower theophylline levels by increasing liver enzyme activity, potentially making the medicine less effective. Quitting smoking or reducing cigarettes can sometimes increase theophylline levels, raising side-effect risk.

• If you plan to quit smoking, inform your clinician/pharmacist.
• If you start or restart smoking, also seek advice.

Safety profile: side effects and when to get help

Like all medicines, Theo-24 Sr can cause side effects. The risk of certain effects increases when theophylline levels become too high. Sustained-release tablets are designed to reduce peaks, but individual sensitivity and interactions can still cause problems.

Common or mild side effects

• nausea or stomach discomfort
• headache
• heartburn or indigestion
• feeling “jittery”
• restlessness
• difficulty sleeping (insomnia), especially if taken late

Serious side effects (seek urgent medical advice)

Contact urgent care or emergency services if you experience:

• seizures
• severe or persistent vomiting
• very fast heartbeat, palpitations with dizziness, or fainting
• shaking that is significant or rapidly worsening
• confusion or marked worsening of alertness
• signs of a serious allergic reaction (e.g., swelling of face/lips, severe rash, trouble breathing)

Who should be extra cautious?

• older adults
• people with liver disease
• people with heart rhythm issues
• people taking medicines known to interact with theophylline
• people who smoke or have recently stopped/start smoking

Your pharmacist may advise about blood tests if you are at increased risk or if doses are changing.

Practical use tips (helping you get the best results safely)

• Keep a consistent routine: take your dose at the same time each day.
• Don’t change smoking habits suddenly without checking with your healthcare team.
• Check before starting new medicines: ask your pharmacist about interactions, especially antibiotics, antifungals, and medicines for colds/flu.
• Limit caffeine: tea, coffee, energy drinks, and some pre-workout products can add to jitteriness and sleep problems.
• Monitor symptom control: if breathlessness is not improving or is worsening, seek advice rather than adjusting dose yourself.
• Track side effects: if you develop tremor, palpitations, nausea, or insomnia, tell your clinician promptly.

Alternative options in the UK

Depending on your diagnosis (e.g., COPD or asthma) and severity, alternative medicines may include:

• Inhaled corticosteroids and bronchodilators (for asthma and COPD control).
• Long-acting bronchodilators (e.g., LABA/LAMA combinations) for COPD.
• Leukotriene receptor antagonists (more relevant for some asthma types).
• Other medicines may be considered if theophylline is not tolerated or interactions make it difficult to use safely.

Your pharmacist/clinician can explain what options are most appropriate for your condition and whether Theo-24 Sr is the right step for you.

Market and legal context (United Kingdom)

In the UK, medicines are regulated by the Medicines and Healthcare products Regulatory Agency (MHRA). Healthcare providers and pharmacies follow UK-specific standards for medicine quality, safety information, and patient guidance.

Treatment for chronic respiratory conditions commonly follows national guidance and local NHS/primary care pathways. The use of theophylline is typically considered when it fits the clinical picture and when safe use can be supported (for example, through dose adjustment and interaction checks).

Advice and recommendations can be updated as evidence develops. Always use the most up-to-date information provided by your healthcare team or pharmacist.

Recent guidance and clinical considerations

UK respiratory care guidance continues to emphasise:

• Inhaler optimisation and correct technique as a priority for asthma and COPD.
• Using medicines with a favourable risk–benefit balance.
• Reviewing medicines that require careful monitoring, including theophylline, particularly where interactions or side-effect risk are higher.

For theophylline specifically, clinicians often consider:

• The potential for drug interactions and variable metabolism (including effects of smoking).
• Whether any benefit is expected compared with optimising inhaled therapy or other add-ons.
• Whether monitoring (including theophylline levels) is needed based on individual risk.

Delivery and availability (UK online pharmacy)

Availability of Theo-24 Sr can vary depending on the strength and formulation. Many online pharmacies in the UK aim to dispatch orders promptly once verified.

• Delivery times: commonly depend on the courier service and your location (UK mainland vs. remote areas).
• Stock checks: popular strengths may be held in stock more consistently; if out of stock, suppliers may be used.
• Packaging: medicines are typically delivered in secure packaging to protect tablets/capsules.

If you need Theo-24 Sr urgently, check with the pharmacy’s delivery information before placing an order.

Storing Theo-24 Sr

• Keep in the original package to protect from light and moisture.
• Store at the recommended temperature on the label.
• Keep out of the sight and reach of children.
• Do not use after the expiry date on the pack.

Frequently Asked Questions (FAQ)

1) Is Theo-24 Sr the same as regular theophylline?

No. “Sr” indicates sustained release. This means it releases the medicine more slowly over time. Do not switch between products unless advised, as dosing and release profiles may differ.

2) How long does it take to work?

Some people notice symptom improvement within days, but consistent long-term control is usually assessed over weeks. If your breathing symptoms are worsening, contact your healthcare team promptly.

3) What should I do if I miss a dose?

Follow the instructions on the medicine label or advice from your pharmacist. In general, if it’s close to the next dose, you may be told to skip the missed one—do not double up unless instructed.

4) Can I take Theo-24 Sr with my inhalers?

Many people use theophylline alongside inhaled treatments. However, the exact combination depends on your diagnosis. If you have questions about your inhaler schedule, ask your pharmacist.

5) Why do doctors sometimes check blood levels?

Theophylline can have variable blood concentrations and a relatively narrow safety range. Blood tests may help confirm that levels are within a safer, effective range—especially when starting, changing dose, or when interactions occur.

6) Can I drink coffee or tea?

You can usually still have some caffeine, but too much may worsen side effects such as tremor, restlessness, or insomnia. Aim for moderation and keep intake consistent.

7) What if I get side effects like palpitations or shaking?

These may be signs of theophylline levels being too high or sensitivity to the medicine. Stop taking further doses and seek urgent medical advice (or call emergency services if severe symptoms occur).

8) Are there people who should not take it?

Not everyone is suitable. People with certain heart rhythm problems, significant liver impairment, seizure risk, or those taking interacting medicines may need alternative treatment or close monitoring. Discuss your medical history with your healthcare professional.

9) Can I take it during pregnancy or while breastfeeding?

Theophylline use during pregnancy or breastfeeding should be discussed with a clinician who can assess benefits and risks for you and your baby. Do not start or stop without guidance.

10) Does Theo-24 Sr affect driving or operating machinery?

Most people do not have problems, but side effects such as dizziness, palpitations, or sleep disruption could affect alertness. If you feel unwell or lightheaded, avoid driving and seek medical advice.

Key takeaways

• Theo-24 Sr is a sustained-release theophylline medicine used for long-term symptom control in selected chronic respiratory conditions.
• It works by helping open airways and reduce airway narrowing.
• Safety depends on careful use: watch for side effects and consider interactions, especially with other medicines, alcohol, and smoking.
• If symptoms worsen or you develop serious side effects (e.g., seizures, severe palpitations), seek urgent medical attention.

If you have any questions about your specific dose or how Theo-24 Sr fits with your other medicines, your pharmacist can provide personalised advice.