Relafen vs Diclofenac

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For patients experiencing arthritis or other types of chronic pain, certain drugs that inhibit the production of compounds in the body linked to inflammation and pain, called prostaglandins, can help in managing discomfort and improving quality of life. Relafen and Diclofenac are two such nonsteroidal anti-inflammatory drugs (NSAIDs) often prescribed for these conditions. Both impact prostaglandin production but do so through slightly different mechanisms. Relafen (nabumetone) works by reducing levels of certain chemicals that cause fever, pain, and inflammation in the body. Diclofenac is classified as an acetic acid derivative; it functions by inhibiting both COX-1 and COX-2 enzymes which are responsible for producing prostaglandins leading to inflammation and pain.

What is Relafen?

Nabumetone (the generic name for Relafen) is a nonsteroidal anti-inflammatory drug (NSAID), which marked a substantial development upon the first class of NSAIDs. Nabumetone was first approved by the FDA in 1991. Relafen works by inhibiting prostaglandins, chemicals that cause inflammation and pain in the body. It is prescribed for relief from symptoms associated with rheumatoid arthritis and osteoarthritis, including inflammation, swelling, stiffness, and joint pain.

On the other hand, Diclofenac belongs to an older class of NSAIDs but has proven very effective over time. Although it operates on similar principles as nabumetone by reducing substances in the body causing pain and inflammation, diclofenac tends to have stronger effects but also results in more side effects such as gastrointestinal issues compared to newer drugs like nabumetone.

What conditions is Relafen approved to treat?

Relafen (generic name Nabumetone) is approved for the treatment of different types of pain and inflammation:

  • Osteoarthritis, a common form of arthritis that causes pain and stiffness in your joints
  • Rheumatoid arthritis, an autoimmune disease that can cause joint pain and damage throughout your body Unlike Prozac, it's also used as an anti-inflammatory drug which reduces hormones causing inflammation and pain in the body.

How does Relafen help with these illnesses?

Relafen helps manage pain and inflammation by inhibiting the production of certain chemicals called prostaglandins in your body. It does this by blocking an enzyme called cyclooxygenase (COX), which is responsible for converting arachidonic acid into prostaglandins. Prostaglandins play a crucial role in promoting inflammation, fever, and pain signals in your body. People with conditions like osteoarthritis or rheumatoid arthritis often have higher levels of these substances. Therefore, by reducing the concentration of prostaglandins, Relafen can limit the symptoms associated with these conditions and help patients improve their quality of life.

In comparison, Diclofenac works similarly to Relafen as it also blocks COX enzymes leading to lower production of prostaglandins thus relieving pain and inflammation. However, it tends to be more potent than Relafen but might come with a slightly increased risk for cardiovascular side effects.

What is Diclofenac?

Diclofenac is a non-steroidal anti-inflammatory drug (NSAID) that functions by reducing substances in the body that cause pain and inflammation. It works by inhibiting cyclooxygenase, an enzyme involved in prostaglandin production which plays a key role in causing inflammation and pain. Diclofenac was first approved by the FDA in 1988.

As Diclofenac is not a narcotic or opioid analgesic, it does not lead to addiction or physical dependence. Its action on cyclooxygenase means its side-effect profile is different from opioids; notably it doesn't typically cause sedation, constipation, or respiratory depression - common side effects of narcotics such as codeine.

The effectiveness of Diclofenac can be advantageous for pain management, especially when over-the-counter NSAIDs like ibuprofen are ineffective or contraindicated.

What conditions is Diclofenac approved to treat?

Diclofenac, an NSAID (Non-Steroidal Anti-Inflammatory Drug), is approved for the management of various conditions including:

How does Diclofenac help with these illnesses?

Diclofenac is a non-steroidal anti-inflammatory drug (NSAID) that functions by inhibiting the production of prostaglandins, substances in the body that cause inflammation and pain. This effect makes it particularly effective for conditions such as arthritis. Diclofenac works by providing higher levels of pain relief compared to other NSAIDs, including Relafen. It's action on cyclooxygenase enzymes (COX-1 and COX-2), which are involved in the production of prostaglandins, play key roles in its effectiveness as an analgesic and anti-inflammatory drug. While both drugs are used to manage similar conditions, Diclofenac is often prescribed when patients do not respond well to other NSAIDs like Relafen or need stronger relief from their symptoms.

How effective are both Relafen and Diclofenac?

Both nabumetone (Relafen) and diclofenac are widely-used nonsteroidal anti-inflammatory drugs (NSAIDs), with their initial approval by the FDA separated by just a few years. Since they interact with different enzymes in the body, they may be prescribed under varying conditions. The effectiveness of nabumetone and diclofenac in managing symptoms of rheumatoid arthritis was directly compared in a randomized controlled trial conducted in 1993; both drugs demonstrated similar efficacy as well as safety profiles.

A review published in 2002 focused on nabumetone's role within NSAID therapy, suggesting that it effectively reduces inflammation and pain, commencing from the first days of treatment. It showed favorable side effect profiles over other many NSAIDs due to its unique mechanism of action which causes less gastrointestinal toxicity - an important consideration for long-term users or those at risk of developing gastric ulcers. Nabumetone is commonly prescribed for osteoarthritis and rheumatoid arthritis with an optimal daily dose thought to be around 1-2g.

In contrast, a meta-analysis performed in 2016 indicated that while diclofenac seems more potent than placebo at relieving pain associated with conditions like osteoarthritis, its potency appears equivalent to other common NSAIDs such as ibuprofen or naproxen. However, unlike most NSAIDs which inhibit both COX-1 and COX-2 enzymes equally, diclofenac has shown greater specificity toward COX-2 inhibition thereby offering potentially lesser gastrointestinal side effects but higher cardiovascular risks when used long term or at high doses. Diclofenac may therefore be suited best for patients who require strong short-term relief from severe inflammatory pain but aren't suitable candidates for opioids or steroidal medications.

abstract image of a researcher studying a bottle of drug.

At what dose is Relafen typically prescribed?

Oral dosages of Relafen range from 1,000–2,000 mg/day divided into two doses. However, studies have shown that a dose of 1,000 mg per day is often sufficient for managing mild to moderate pain and inflammation in most adults. For Diclofenac on the other hand, the typical oral dosage ranges from 100-150 mg per day divided into 2-3 doses depending on the specific condition being treated. The maximum dosage that should not be exceeded for either medication is determined by your healthcare provider based on your individual needs and response to therapy but generally does not exceed 2000mg/day for Relafen or 200mg/day for Diclofenac. Always take these medications under direct guidance from a healthcare professional.

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At what dose is Diclofenac typically prescribed?

Diclofenac treatment is usually initiated at a dosage of 100–150 mg per day, divided into two or three doses. The dose can be increased up to a maximum of 200 mg/day if required, depending on the severity of pain and inflammation. This should be split into several smaller doses throughout the day, for instance - four doses of 50mg each spaced about six hours apart. If there's no significant response to the treatment after a few weeks at this maximum level, your doctor may reconsider your medication strategy.

What are the most common side effects for Relafen?

Common side effects of Relafen (nabumetone) include:

  • Upset stomach, nausea, and diarrhea
  • Indigestion or heartburn
  • Drowsiness, dizziness
  • Skin rash or itching
  • Fluid retention and swelling
  • Ringing in the ears

On the other hand, Diclofenac may lead to:

  • Nausea
  • Heartburn or indigestion
  • Diarrhea
  • Headache and dizziness
  • Rash
  • Fluid retention resulting in swollen ankles and feet.

Please remember that these are just possible side effects. Not everyone who takes these medications will experience them. However, if you do encounter any symptoms while on medication it's always a good idea to seek medical advice as soon as possible.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Relafen?

Relafen (nabumetone) and Diclofenac are both nonsteroidal anti-inflammatory drugs (NSAIDs), but they can have different side effects. Serious side effects that may occur from Relafen use include:

  • Signs of an allergic reaction: hives, difficulty breathing, swelling in your face or throat
  • Symptoms suggesting cardiac trouble such as chest pain spreading to the jaw or shoulder, sudden numbness or weakness on one side of the body, shortness of breath
  • Indicators of stomach bleeding like bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds
  • Liver problems: nausea, upper stomach pain, itching/tiredness/loss of appetite/dark urine/clay-colored stools/jaundice
  • Skin reactions: fever/sore throat/burning eyes/skin pain/red/purple skin rash with blistering and peeling.

In contrast with Diclofenac these symptoms might be less common but it is essential to immediately consult a healthcare provider if you experience any severe adverse reactions. It's also important to remember everyone's body reacts differently to medications; what works well for one person may not work as effectively for another.

What are the most common side effects for Diclofenac?

Diclofenac, a nonsteroidal anti-inflammatory drug (NSAID), often results in the following side effects:

  • Indigestion, gas, stomach pain
  • Nausea and vomiting
  • Diarrhea or constipation
  • Headache or dizziness
  • Drowsiness or fatigue
  • Ringing in the ears
  • Rash More serious but less common side effects include fluid retention leading to swelling (edema), high blood pressure, heart palpitations, chest pain, liver problems demonstrated by jaundice (yellowing of the skin and eyes), kidney problems resulting in changes in urination frequency and amount. Also important to note is that long-term use may increase your risk of heart attack or stroke. It's crucial to discuss these potential risks with your healthcare provider before starting treatment with diclofenac.

Are there any potential serious side effects for Diclofenac?

Diclofenac, like any other medication, can cause a range of side effects. Some of the more severe adverse reactions to look out for include:

  • Signs of an allergic reaction such as hives; difficulty breathing; swelling in your face or throat.
  • Severe skin reactions like fever, sore throat, burning eyes, red or purple skin rash with blistering and peeling which could be symptoms of Stevens-Johnson syndrome or toxic epidermal necrolysis.
  • Indications of liver problems including nausea, upper stomach pain or discomfort that might radiate to the back, fatigue and loss of appetite accompanied by darkened urine and jaundice (yellowing) in your eyes and skin.
  • Signs implying kidney issues such as lower volume than usual urination or no urination at all; painful or difficult urination paired with swelling in feet/legs due to fluid retention. If you experience any such signs while on Diclofenac therapy it is advised you seek immediate medical attention.

Contraindications for Relafen and Diclofenac?

Both Relafen and Diclofenac, along with most other nonsteroidal anti-inflammatory drugs (NSAIDs), may worsen symptoms of certain conditions such as heart disease or high blood pressure. If you notice any severe side effects like chest pain, shortness of breath, weakness on one part of your body, slurred speech or sudden vision changes while taking these medications, please seek immediate medical attention.

Neither Relafen nor Diclofenac should be taken if you are already using aspirin to prevent heart attacks or stroke. Always inform your physician about all the medications that you are currently taking; Aspirin might interfere with the working mechanism of NSAIDs like Relafen and Diclofenac. Also note that these medicines might increase your sensitivity to sunlight which can lead to sunburns; use sunscreen and wear protective clothing when going outdoors.

How much do Relafen and Diclofenac cost?

For the brand name versions of these drugs:

  • The price for 60 tablets of Relafen (500 mg), also known as Nabumetone, averages around $250 which works out to approximately $8-$16/day depending on your dose.
  • The price for 30 tablets of Voltaren (50 mg), a popular brand-name version of Diclofenac, averages around $200. This works out to approximately $6.67/day.

Thus, if you are in the higher dosage range for Relafen (i.e., 1000 mg/day or higher), then brand-name Diclofenac is less expensive on a per-day treatment basis. Please note that cost should not be a primary consideration when determining which drug is right for you.

For the generic versions:

  • Generic Nabumetone (500mg) can be obtained in packs ranging from 30 tablets and above with daily costs between about $.80 and $.90 at dosages ranging from 500mg to 1500mg.
  • Generic Diclofenac comes in several forms including oral tablet form where it's available in packs starting from as low as fifteen up to one hundred with daily costs averaging somewhere between $.70 and .$.90 per day based on typical doses ranging from fifty milligrams up to two hundred milligrams.

Popularity of Relafen and Diclofenac

Nabumetone, also known by the brand name Relafen, and Diclofenac are both nonsteroidal anti-inflammatory drugs (NSAIDs) commonly used to help relieve pain and inflammation.

In 2020, nabumetone was prescribed to approximately 1 million people in the US. This accounted for just over 1% of NSAID prescriptions across the country. Despite its lower usage compared to other NSAIDs, nabumetone has remained relatively steady in prevalence since it first came onto the market.

Diclofenac on the other hand is widely recognized globally due to its effectiveness as an analgesic and anti-inflammatory agent with a well-established safety profile. It was prescribed to about 6 million people in the USA during 2020, which equates around 7% of all NSAID prescriptions nationwide. The use of diclofenac has been increasing gradually over time and remains one of the most popularly prescribed drugs within this class.


Both Relafen (nabumetone) and Diclofenac are effective nonsteroidal anti-inflammatory drugs (NSAIDs) used to manage pain, inflammation, and stiffness caused by conditions such as arthritis. They have been backed by numerous clinical studies indicating their effectiveness over placebo treatments. However, they should not be combined without careful consideration due to potential drug interactions.

Relafen functions mainly as a COX-2 inhibitor with less effect on COX-1 enzymes, which means it might cause fewer gastrointestinal side effects compared to other NSAIDs. Diclofenac is potent but can affect both the COX-1 and COX-2 enzymes leading potentially more gastrointestinal side effects.

While Relafen is typically taken once or twice daily, diclofenac may need to be taken up to four times per day depending on the condition being treated. Both drugs are available in generic forms that provide cost savings for patients paying out of pocket.

The side effect profiles are similar between these two medications; however, because Diclofenac affects both types of cyclooxygenase enzymes, some people may experience more digestive system-related side effects like nausea or stomach upset compared with those taking Relafen. As always when starting new medication treatment plans, patients must monitor any changes in symptoms closely and seek medical assistance if adverse reactions occur.