Voltaren-SR

Diclofenac

Method of action: Analgesic, Analgesic Local, Analgetic, Anti-Inflammatory, Antiplatelet, Antipyretic, Antirheumatic, Decongestant, Nonsteroidal Anti-Inflammatory, Ophthalmologicals

Treatment option: Ankylosing Spondylitis, Backache, Pain, Bursitis, Headache, Influenza, Dysmenorrhea, Biliary Colic, Toothache, Colic

Medically reviewed

Marina Burgos

Last updated on 10/01/2026

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Voltaren-SR

What is Voltaren-SR?

Voltaren-SR is a prescription-only medicine whose active compound is Diclofenac, a substance primarily used to reduce pain and inflammation throughout the body. The "SR" designation specifies that this oral medication is manufactured as a modified-release tablet, designed to provide an extended duration of effect. The function of this preparation is systemic, meaning the active substance is absorbed internally and acts across various areas of the body.

Identity, Classification, and Formulation

Voltaren-SR belongs to the family of medicines known as Nonsteroidal Anti-Inflammatory Drugs (NSAIDs), chemically classified as a derivative of phenylacetic acid. The core active substance is Diclofenac Sodium. This medication is in a class recognized for easing discomfort and reducing swelling caused by underlying inflammatory processes.

The key feature of Voltaren-SR is its modified-release design (often termed slow-release or extended-release), which contrasts it with immediate-release tablets. This formulation is engineered to control the rate at which the Diclofenac is released after oral ingestion. Modified-release formulations are intended to help maintain stable therapeutic levels of the drug in the system. This specific design is a differentiating factor, as it helps provide a more consistent anti-inflammatory and analgesic effect over time, which is often utilized in managing chronic inflammatory conditions.

General Purpose and Core Actions

The overarching purpose of Voltaren-SR is the systemic mitigation of the signs of inflammation, which include discomfort, swelling, and redness. Diclofenac achieves this purpose by limiting the synthesis of specific biological messengers called prostaglandins, which are responsible for triggering pain and promoting inflammatory responses. The fundamental benefit is the reduction of these core symptoms through its anti-inflammatory, analgesic (pain-relieving), and antipyretic (fever-reducing) actions.

Regulatory References

Modified-Release Dosage Forms and their Clinical Benefits

What side effects are possible with Voltaren-SR?

Possible Side Effects and Safety Information

Regulatory Classification of Adverse Reactions

The official safety profile for Diclofenac Sodium is structured to classify possible adverse reactions based on the physiological system affected (System-Organ Class) and their documented frequency of occurrence.

Common Reactions: Officially listed effects frequently include Gastrointestinal disorders (such as nausea, dyspepsia, abdominal pain), Nervous system disorders (headache, dizziness), and Hepato-biliary disorders (elevated liver enzymes).
System-Organ Classes Involved: Adverse reactions are cataloged within major groupings, including Gastrointestinal disorders, Cardiac disorders, Vascular disorders, Nervous system disorders, and Skin and subcutaneous tissue disorders.

Serious Adverse Reactions and Safety Constraints

Official regulatory documents explicitly detail risks classified as serious, which may be rare but are clinically significant. This includes the risk of Serious Cardiovascular Thrombotic Events (such as myocardial infarction and stroke) and Serious Gastrointestinal Adverse Events (including bleeding, ulceration, and perforation).

Exposure-Related Patterns: The risk of serious adverse effects is documented to potentially increase with higher doses and longer duration of treatment. The risk of cardiovascular thrombotic events may begin early in treatment.
Population-Specific Constraints: Regulatory labeling notes specific safety considerations for patient groups, including Older Adults (who have an increased risk of serious GI events) and patients with pre-existing cardiovascular disease.
Safety Restrictions: The medication is contraindicated in patients with established congestive heart failure (NYHA Class II-IV), a history of Gastrointestinal bleeding or ulceration, and a history of allergic-type reactions (asthma, urticaria) after taking aspirin or other NSAIDs.

Summary of Regulatory Safety Structure

The regulatory safety structure formally defines the spectrum of risks, ensuring that potential adverse events are categorized by both the affected body system and their likelihood. This profile adheres to the principle that the lowest effective dose should be used for the shortest possible duration to help mitigate documented risks.

Overdose and Emergency Response

Overdose and When to Seek Help

Voltaren-SR (diclofenac extended-release) overdose can occur if more than the prescribed dosage is taken. Since this is a sustained-release formulation, symptoms may be delayed. Immediate medical attention is crucial if an overdose is suspected, even if symptoms are not yet present.

Symptoms of Overdose

The most common symptoms of an acute overdose are generally related to the gastrointestinal and nervous systems. These can include:

System	Symptoms
Gastrointestinal	Nausea, vomiting (sometimes with blood), stomach pain, abdominal bleeding, and diarrhea.
Nervous System	Headache, dizziness, drowsiness, confusion, agitation, or, in severe cases, seizures and coma.

Other serious, though less frequent, effects can involve the cardiovascular or renal systems, such as high blood pressure, decreased urine output, or acute kidney failure.

When to Seek Immediate Help

If you believe you or someone else has taken too much Voltaren-SR, contact a poison control center immediately or proceed to the nearest emergency department. Treatment for a diclofenac overdose is primarily supportive, as there is no specific antidote. Medical professionals may monitor vital signs, perform tests, and administer activated charcoal to reduce drug absorption if the ingestion was recent.

Therapeutic Uses of Voltaren-SR

What Voltaren-SR Treats: Main Uses and Benefits

Voltaren-SR is used to provide systemic symptomatic relief across therapeutic domains characterized by disruptive inflammatory pain and swelling. Its modified-release formulation may assist with providing supportive relief when symptoms interfere with routine activities, contributing to maintaining a sense of stability. This medication is considered relevant for easing symptoms related to inflammatory or irritative states.

Key Therapeutic Applications

This medication is commonly used in conditions marked by long-term or recurrent inflammation, such as rheumatoid arthritis, osteoarthritis, and ankylosing spondylitis, as well as in acute contexts like flare-ups of gout or significant pain and swelling following orthopaedic or dental surgery. The medication is applied in addressing conditions involving episodic or fluctuating manifestations, such as primary dysmenorrhoea (menstrual cramps).

The medication may assist with managing symptom clusters that may become intense or disruptive. The supportive benefit is often described as providing symptomatic relief that helps patients cope more steadily with symptom fluctuations.

Quick Fact: Relief for Inflammatory Discomfort

Voltaren-SR is applied across domains where additional symptomatic support is needed, primarily when symptoms of pain and swelling interfere with daily comfort. The modified-release design may assist with providing supportive relief when symptoms interfere with routine activities, contributing to maintaining a sense of stability.

Eligibility and Restrictions for Use

Who can and cannot use Voltaren-SR? — Official Regulatory Information

Eligibility for Voltaren-SR (diclofenac sodium extended-release) is strictly defined by major contraindications and patient risk factors as stated in official regulatory documents. This medicine is generally intended for adults.

Classification	Eligibility Rule
Absolute Contraindication	Patients with known hypersensitivity to diclofenac, aspirin, or other NSAIDs (which precipitate asthma or hives); active gastrointestinal ulceration, bleeding, or perforation; severe hepatic or renal failure; the last trimester of pregnancy; or for peri-operative pain in the setting of Coronary Artery Bypass Grafting (CABG) surgery.
Age-Related	Voltaren-SR (prolonged-release dosage strength) is not suitable or not established for use in children and adolescents (typically under 14 or 16 years old).
Restricted/Not Recommended	Use is generally not recommended in patients with established cardiovascular disease (e.g., Congestive Heart Failure NYHA Class II-IV, ischemic heart disease). Caution is required for patients who are breastfeeding, the elderly, and those with existing mild to moderate hepatic or renal impairment.

What should I know about interactions with other medicines?

Voltaren-SR Interactions with other medicines and products

The interaction profile of Voltaren-SR is defined by specific pharmacokinetic and pharmacodynamic patterns documented in official regulatory sources. Concomitant use with other medicinal products may result in altered plasma concentrations of either Voltaren-SR or the co-administered drug, or lead to additive physiological effects.

Mandatory Restrictions and Prohibitions

The medication is strictly contraindicated for the treatment of perioperative pain related to coronary artery bypass graft (CABG) surgery. Due to the potential for severe additive adverse effects, concurrent use with other systemic Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) is officially avoided.

Official Interaction Outcomes

Exposure Alteration: Voltaren-SR co-administration is documented to increase the serum concentration of drugs such as Lithium and Digoxin by reducing their clearance. Conversely, the strong CYP inhibitor Voriconazole officially increases the plasma exposure of Diclofenac.
Bleeding Risk: Co-administration with Anticoagulants, Antiplatelet Agents, Oral Corticosteroids, and SSRIs/SNRIs significantly increases the risk of serious bleeding due to additive pharmacodynamic effects.
Antihypertensive Interference: Voltaren-SR may diminish the antihypertensive effect of Diuretics, ACE Inhibitors, and ARBs. This combination carries a specific caution for elderly, volume-depleted, or renal-impaired patients due to a heightened risk of renal function deterioration.
Substance/Timing Rules: To avoid potential interference, low-dose Aspirin taken for cardioprotection must be separated by at least 2 hours. Combining the medicine with Alcohol or specific Herbal Supplements (e.g., Ginseng, Ginkgo Biloba) is officially noted to increase the risk of serious gastrointestinal problems.

Mechanism of Action

Molecular Blockade of Cyclooxygenase (COX) Enzymes

The mechanism of action involves the interaction with specific biochemical pathways and the modulation of key regulatory enzymes at the molecular level. Its mechanistic activity is characterized by the non-selective, reversible inhibition of the Cyclooxygenase ( COX-1 and COX-2) enzymes. This inhibition directly suppresses the rate-limiting step in the Arachidonic Acid Cascade, which is the pathway responsible for generating prostanoids (such as PGE2). The resulting biochemical suppression underlies the subsequent physiological modulations.

️ Modulation of Nociceptor and Vascular Activity

By limiting prostanoid production, the drug directly reduces the amount of PGE2 in relevant physiological contexts, including the peripheral environment and the central nervous system. Peripherally, this decrease is associated with reduced nociceptor sensitization and modulation of vascular responses. Centrally, the mechanism facilitates the adjustment of the hypothalamic temperature set point from a state induced by PGE2 concentration. The modified-release design supports the maintenance of this sustained enzyme inhibition.

Dosage and Administration Information

How to Use Voltaren-SR: Official Administration Principles

Voltaren-SR (Diclofenac Sodium prolonged-release tablet) is used according to established administration principles, which focus on its modified-release design for systemic delivery. The route of administration is strictly oral.

Administration and Dosage Regimen

The standard adult dosing schedule for Voltaren-SR is 100 mg taken once daily. This once-daily frequency is established by the tablet's engineering, which releases the active substance over an extended period. The overall use is guided by the principle of maintaining the lowest effective dose for the shortest duration necessary to achieve symptomatic control, with a total diclofenac daily dose generally not exceeding 150 mg. The need for continued treatment must be re-evaluated periodically.

Essential Administration Instructions

To ensure the controlled-release properties function correctly, the tablet must be swallowed whole with liquid and must not be split, crushed, chewed, or dissolved. The tablet can be taken with or after food. If symptoms are most pronounced at night or in the morning, the dose is preferably taken in the evening to align with symptom presentation.

Population-Specific Usage

The 100 mg prolonged-release strength is not suitable for children and adolescents under 18 years of age. For older adults, while no specific initial dose reduction is mandated, the use of the lowest effective dose is recommended, particularly in frail patients. If a dose is missed, patients should resume their next scheduled dose at the usual time and not take a double dose to compensate.

Recent Clinical Evidence

Voltaren-SR, an extended-release formulation of diclofenac sodium, is indicated for the relief of the signs and symptoms of osteoarthritis (OA) and rheumatoid arthritis (RA). Clinical evidence supporting its use focuses on efficacy and the safety profile associated with long-term use and the extended-release mechanism.

Efficacy and Symptom Relief

Studies examining the use of extended-release diclofenac in conditions like OA have shown associations between treatment and observed improvements in pain and physical function scores, such as those measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). The extended-release formulation is designed to provide sustained levels of the medication over a prolonged period.

Condition	Typical Efficacy Metrics Evaluated
Osteoarthritis (OA)	WOMAC Pain and Physical Function Subscales, Patient Global Assessment
Rheumatoid Arthritis (RA)	Swollen Joint Count, Tender Joint Count, Disease Activity Scores

Safety Considerations

As with all nonsteroidal anti-inflammatory drugs (NSAIDs), research has consistently highlighted the potential for gastrointestinal (GI) and cardiovascular (CV) risks. The extended-release formulation does not eliminate these systemic risks, and regulatory bodies recommend using the lowest effective dose for the shortest possible duration to minimize the potential for adverse events.

Recent research has also explored variability in diclofenac metabolism, suggesting that differences in drug-metabolizing enzymes may contribute to individual variations in response and risk of side effects across different patient populations.

Frequently Asked Questions (FAQ)

Common questions about Voltaren-SR (FAQ)

Q: What is Voltaren-SR and how does it work?

Voltaren-SR is a brand name for a medicine containing the active ingredient diclofenac sodium, which belongs to a class of drugs called Nonsteroidal Anti-inflammatory Drugs (NSAIDs). The 'SR' stands for Sustained Release. Diclofenac works by blocking the production of certain natural substances (prostaglandins) in the body that cause inflammation, pain, and fever. By reducing these substances, Voltaren-SR helps to relieve pain and decrease swelling.

Q: What conditions is Voltaren-SR typically used to treat?

Voltaren-SR is commonly used to manage pain and inflammation associated with a variety of conditions, including:

Osteoarthritis (a type of arthritis that causes the breakdown of joints)
Rheumatoid arthritis (an autoimmune disease that causes joint inflammation)
Ankylosing spondylitis (a type of arthritis that affects the spine)
Other painful conditions affecting the joints, muscles, or bones.

Q: How should I take Voltaren-SR sustained-release tablets?

Take Voltaren-SR tablets exactly as prescribed by your healthcare provider.
The sustained-release tablets should be swallowed whole with a full glass of water. Do not crush, chew, or split them, as this will affect the sustained-release mechanism and may increase the risk of side effects.
It is generally recommended to take the tablets with food or milk to help reduce the possibility of stomach upset.
Do not take more than the recommended dosage.

Q: What are some common side effects of Voltaren-SR?

Common side effects of diclofenac, the active ingredient in Voltaren-SR, may include:

Stomach upset, such as nausea, indigestion, or heartburn
Diarrhea or constipation
Headache
Dizziness
Fluid retention (swelling of the hands or feet)
Elevated liver enzymes (detected through blood tests)

If you experience severe or persistent side effects, contact your healthcare provider.

Q: Can Voltaren-SR interact with other medications?

Yes, Voltaren-SR can interact with various other medications. It is important to inform your healthcare provider about all prescription, over-the-counter, and herbal supplements you are currently taking. Notable interactions include:

Other NSAIDs (e.g., ibuprofen, naproxen) as combining them increases the risk of serious stomach problems.
Blood thinners (anticoagulants), which may increase the risk of bleeding.
Certain blood pressure medications (e.g., diuretics, ACE inhibitors).
Lithium or methotrexate, as diclofenac may increase the levels of these drugs in the blood.

Your healthcare provider can review your medications and adjust dosages as needed.

Q: Is Voltaren-SR safe to use during pregnancy?

Use of Voltaren-SR (diclofenac) is generally not recommended during pregnancy, especially during the third trimester. NSAIDs taken late in pregnancy can cause serious problems for the unborn baby, including harm to the heart and kidneys. If you are pregnant, planning to become pregnant, or breastfeeding, you should discuss the risks and benefits of taking Voltaren-SR with your doctor.

How should Voltaren-SR be stored and disposed of?

How to Store and Dispose of Voltaren-SR?

Regulatory documents outline specific requirements for the storage, protection, and disposal of Diclofenac Sodium modified-release tablets to ensure product stability and safety.

Storage Requirement	Official Guidance
Temperature Range	Store at controlled room temperature, typically between 20 C to 25 C. Do not freeze and do not store above the maximum specified limit (e.g., 30 C).
Environmental Protection	Keep the tablets in the original container, protected from heat, moisture, and light.
Child Safety	Mandatory to keep the medication out of the sight and reach of children.
Disposal	Do not dispose of expired or unused tablets in household waste or flush them down the toilet. Return them to a pharmacy or authorized collection site for safe disposal.