Theophylline Tablet Side Effects in Pakistan

Theophylline side effects are mostly related to serum levels — due to the narrow therapeutic index the risk of toxicity and side effects is real. This guide details common, serious, and emergency signs.

Compiled by the PakVita Editorial Team · AI-assisted drafting with editorial review · Sourced from DRAP, WHO, BNF · Last updated: 2026-06-17

Side Effects

Quick Answer

Common side effects of Theophylline include nausea, vomiting, headache, insomnia, and tachycardia — mostly occur at high serum levels. Serious toxicity (arrhythmias, seizures) occurs above 20 mg/L but can also occur within the therapeutic range. Seek emergency care immediately for severe nausea/vomiting, irregular heartbeat, or fits.

Side Effects at a Glance

Common

Nausea (matli)
Vomiting (qai)
Headache (sar dard)
Insomnia
Tachycardia — fast heartbeat / palpitations
Tremor (hand trembling)
Mild diuresis (frequent urination)

Serious — See a Doctor

Arrhythmias — atrial and ventricular (irregular/fast heartbeat — cardiac toxicity)
Seizures / convulsions (neurological toxicity — EMERGENCY)
Severe nausea/vomiting
Agitation, hallucinations, confusion (neurological toxicity)
Hypotension (falling blood pressure)
Rhabdomyolysis (muscle breakdown — severe toxicity)

When to See a Doctor Immediately

Severe nausea/vomiting
Irregular or very fast heartbeat (arrhythmia — EMERGENCY)
Fits / convulsions
Agitation, confusion, hallucinations (neurological toxicity)
Persistent tremors not related to dose
If stopping smoking or starting a new medicine — consult your doctor first

Theophylline Tablet Side Effects (Nuksanat)

Theophylline (Theo-Dur, Phyllocontin) side effects are mostly related to serum levels. Due to the narrow therapeutic index there is a serious risk of toxicity and side effects. Common and serious effects are detailed on this page.

Common Side Effects (Aam Nuksanat)

These effects generally occur above the therapeutic range or at the start:

Nausea (matli) — most common early sign
Vomiting (qai)
Headache (sar dard)
Insomnia
Fast heartbeat / palpitations (tachycardia)
Hand trembling (tremor)
Frequent urination (mild diuresis)
Heartburn (gastro-oesophageal reflux — uncommon)

If these symptoms occur, inform your doctor immediately — checking serum levels may be necessary.

Serious Side Effects (Sanjeedah Nuksanat — Toxicity)

Toxicity typically occurs above 20 mg/L — but can also occur within the therapeutic range (especially acute toxicity):

Side Effect	Action
Severe nausea/vomiting (early warning)	Immediate doctor — have levels checked
Irregular / fast heartbeat (arrhythmia)	EMERGENCY — call 1122
Fits / seizures / convulsions	EMERGENCY — call 1122
Agitation, hallucinations, confusion	Immediate doctor — neurological toxicity
Hypotension (falling blood pressure)	EMERGENCY
Muscle breakdown (rhabdomyolysis)	Severe toxicity — EMERGENCY

Acute toxicity > chronic toxicity: Acute overdose is more dangerous than chronic toxicity.

Theophylline Toxicity — Level Chart

Serum Level	Risk
10–20 mg/L	Therapeutic — low risk
20–30 mg/L	Mild toxicity — nausea, tachycardia
> 30 mg/L	Severe toxicity — arrhythmias, seizures possible

Factors That Increase Toxicity Risk

Stopping smoking — levels rise (most common cause in Pakistan)
Starting ciprofloxacin, erythromycin, or clarithromycin
Illness/fever (reduced clearance)
Liver disease, heart failure
Old age (elderly)
High-fat meal with SR preparations

Reporting Side Effects

If you notice any unexpected side effect, report it on the DRAP pharmacovigilance portal: https://www.dra.gov.pk/pharmacovigilance

When to See Doctor Immediately (Emergency Signs)

Irregular or very fast heartbeat → arrhythmia → 1122
Fits / convulsions → EMERGENCY → 1122
Severe persistent vomiting → early toxicity → immediate doctor
Agitation, hallucinations, confusion → neurological toxicity

The information in this guide is for educational purposes only. If you notice any side effect, contact your doctor or pharmacist.

Frequently Asked Questions

Theophylline ke common side effects kya hain?

Common side effects include nausea, vomiting, headache, insomnia, fast heartbeat, and hand trembling. These mostly occur at high serum levels — inform your doctor immediately.

Theophylline toxicity ke signs kya hain?

Early: severe nausea/vomiting. Serious: irregular heartbeat (arrhythmia), fits/seizures (severe — life-threatening), agitation, hallucinations. Typically occurs above 20 mg/L levels.

Kya theophylline fits cause kar sakti hai?

Yes — seizures can occur in severe theophylline toxicity. This is a medical emergency — call 1122 immediately.

Theophylline toxicity mein kya karein?

Go to 1122 or the nearest emergency immediately. Treatment: supportive, charcoal (early) — in hospital. Do not attempt to manage at home.

Smoking chhodni se theophylline toxicity kyun hoti hai?

Smoking induces the CYP1A2 enzyme — theophylline levels stay LOW. When smoking stops the enzyme induction decreases → levels RISE → risk of toxicity. Have the dose rechecked by your doctor immediately.

Brand alternatives, same-class options, and other medicines used for the same conditions as Theophylline Tablet.

Used for the same conditions

Other medicines commonly used for asthma and overlapping conditions.

Asthma hub →

Sources

BNF: Theophylline — BMJ Group & Pharmaceutical Press
DRAP Registered Products Database — Drug Regulatory Authority of Pakistan
WHO Model List of Essential Medicines, 23rd ed. (2023) — World Health Organization
British National Formulary (BNF) — BMJ Group & Pharmaceutical Press

Medical disclaimer

This page is for educational use only and does not replace professional medical advice. Always confirm diagnosis, dose, and interactions with a qualified doctor or pharmacist before starting or changing any medicine.