Side Effects of Clinoril (sulindac)

Clinoril (sulindac) is a nonsteroidal anti-inflammatory drug (NSAID) used to treat pain, fever, and inflammation. 

NSAIDs work by reducing the levels of prostaglandins, chemicals produced by the body and that are responsible for pain, fever, and inflammation. Clinoril blocks the enzyme that makes prostaglandins (cyclooxygenase), resulting in lower concentrations of prostaglandins. As a consequence, inflammation, pain, and fever are reduced. 

Common side effects of Clinoril include:

• abdominal pain,
• cramping,
• nausea,
• gastritis,
• rash,
• ringing in the ears, and
• lightheadedness.

Serious side effects of Clinoril include:

• ulcerations of the stomach and small intestine,
• serious gastrointestinal bleeding (signs include abdominal pain, black tarry stools, weakness, and dizziness upon standing),
• liver toxicity, and
• kidney impairment.

Fluid retention, blood clots, heart attacks, high blood pressure (hypertension), and heart failure have also been associated with the use of NSAIDs such as Clinoril.

Drug interactions of Clinoril include lithium, because Clinoril may increase blood levels of lithium and lead to lithium toxicity. 

Clinoril may reduce the blood pressure lowering effects of blood pressure medications such as angiotensin receptor blockers or angiotensin converting enzyme (ACE) inhibitors. 

When Clinoril is used in combination with methotrexate or aminoglycoside antibiotics the blood levels of methotrexate or aminoglycoside may increase, which may lead to more methotrexate or aminoglycoside-related side effects. 

Individuals taking oral blood thinners or anticoagulants should avoid Clinoril because Clinoril also thins the blood, and this may lead to bleeding. 

Persons who consume more than three alcoholic beverages per day are at increased risk of developing stomach ulcers when taking Clinoril or other NSAIDs.

There are no adequate studies of Clinoril in pregnant women. Clinoril is not recommended during pregnancy. 

It is unknown if Clinoril is excreted in breast milk. Consult your doctor before breastfeeding.

Most patients benefit from sulindac and other NSAIDs with few side effects. However, serious side effects can occur and generally tend to be dose related, that is, they occur more frequently with higher doses. Therefore, it is advisable to use the lowest effective dose to minimize side effects.

The most common side effects of sulindac involve the gastrointestinal system, and these are:

• ulcerations of the stomach and small intestine,
• abdominal pain,
• cramping,
• nausea,
• gastritis,
• serious gastrointestinal bleeding, and
• liver toxicity.

Sometimes, ulceration of the stomach and bleeding can occur without any abdominal pain, and black tarry stools, weakness, and dizziness upon standing (orthostatic hypotension) may be the only signs of internal bleeding.

Other important side effects include:

• rash,
• kidney impairment,
• ringing in the ears, and
• lightheadedness.

Sulindac should be avoided by patients with a history of exacerbation of asthma, hives, or other allergic reactions to aspirin or other NSAIDs. Rare but severe allergic reactions have been reported in such individuals. It also should be avoided by patients with peptic ulcer disease or poor kidney function, since this medication can aggravate both conditions. Fluid retention, blood clots, heart attacks, hypertension, and heart failure have also been associated with the use of NSAIDs such as sulindac.

The following adverse reactions were reported in clinical trials or have been reported since the drug was marketed. The probability exists of a causal relationship between Clinoril (sulindac) and these adverse reactions. The adverse reactions which have been observed in clinical trials encompass observations in 1,865 patients, including 232 observed for at least 48 weeks.

Incidence Greater Than 1%

Gastrointestinal

The most frequent types of adverse reactions occurring with Clinoril (sulindac) are gastrointestinal; these include gastrointestinal pain (10%), dyspepsia***, nausea*** with or without vomiting, diarrhea***, constipation***, flatulence, anorexia and gastrointestinal cramps.

Dermatologic

Rash***, pruritus.

Central Nervous System

Dizziness***, headache***, nervousness.

Special Senses

Tinnitus.

Miscellaneous

Edema.

Incidence Less Than 1 in 100

Gastrointestinal

Gastritis, gastroenteritis or colitis. Peptic ulcer and gastrointestinal bleeding have been reported. GI perforation and intestinal strictures (diaphragms) have been reported rarely.

Liver function abnormalities; jaundice, sometimes with fever; cholestasis; hepatitis; hepatic failure.

There have been rare reports of sulindac metabolites in common bile duct “sludge” and in biliary calculi in patients with symptoms of cholecystitis who underwent a cholecystectomy.

Pancreatitis.

Ageusia; glossitis.

Dermatologic

Stomatitis, sore or dry mucous membranes, alopecia, photosensitivity.

Erythema multiforme, toxic epidermal necrolysis, Stevens-Johnson syndrome, and exfoliative dermatitis have been reported.

Cardiovascular

Congestive heart failure, especially in patients with marginal cardiac function; palpitation; hypertension.

Hematologic

Thrombocytopenia; ecchymosis; purpura; leukopenia; agranulocytosis; neutropenia; bone marrow depression, including aplastic anemia; hemolytic anemia; increased prothrombin time in patients on oral anticoagulants.

Genitourinary

Urine discoloration; dysuria; vaginal bleeding; hematuria; proteinuria; crystalluria; renal impairment, including renal failure; interstitial nephritis; nephrotic syndrome.

Renal calculi containing sulindac metabolites have been observed rarely.

Metabolic

Hyperkalemia.

Musculoskeletal

Muscle weakness.

Psychiatric

Depression; psychic disturbances including acute psychosis.

Nervous System

Vertigo; insomnia; somnolence; paresthesia; convulsions; syncope; aseptic meningitis (especially in patients with systemic lupus erythematosus (SLE) and mixed connective tissue disease.

Special Senses

Blurred vision; visual disturbances; decreased hearing; metallic or bitter taste.

Respiratory

Epistaxis.

Hypersensitivity Reactions

Anaphylaxis; angioneurotic edema; urticaria; bronchial spasm; dyspnea.

Hypersensitivity vasculitis.

A potentially fatal apparent hypersensitivity syndrome has been reported. This syndrome may include constitutional symptoms (fever, chills, diaphoresis, flushing), cutaneous findings (rash or other dermatologic reactions - see above), conjunctivitis, involvement of major organs (changes in liver function including hepatic failure, jaundice, pancreatitis, pneumonitis with or without pleural effusion, leukopenia, leukocytosis, eosinophilia, disseminated intravascular coagulation, anemia, renal impairment, including renal failure), and other less specific findings (adenitis, arthralgia, arthritis, myalgia, fatigue, malaise, hypotension, chest pain, tachycardia).

Causal Relationship Unknown

A rare occurrence of fulminant necrotizing fasciitis, particularly in association with Group A ß-hemolytic streptococcus, has been described in persons treated with non-steroidal anti-inflammatory agents, sometimes with fatal outcome.

Other reactions have been reported in clinical trials or since the drug was marketed, but occurred under circumstances where a causal relationship could not be established. However, in these rarely reported events, that possibility cannot be excluded. Therefore, these observations are listed to serve as alerting information to physicians.

Cardiovascular

Arrhythmia.

Metabolic

Hyperglycemia.

Nervous System

Neuritis.

Special Senses

Disturbances of the retina and its vasculature.

Miscellaneous

Gynecomastia.

*** Incidence between 3% and 9%. Those reactions occurring in 1% to 3% of patients are not marked with an asterisk.

ACE-Inhibitors and Angiotensin II Antagonists

Reports suggest that NSAIDs may diminish the antihypertensive effect of ACE-inhibitors and angiotensin II antagonists. These interactions should be given consideration in patients taking NSAIDs concomitantly with ACE-inhibitors or angiotensin II antagonists. In some patients with compromised renal function (e.g., elderly patients or patients who are volume-depleted, including those on diuretic therapy) who are being treated with non-steroidal anti-inflammatory drugs, the co-administration of an NSAID and an ACE-inhibitor or an angiotensin II antagonist may result in further deterioration of renal function, including possible acute renal failure, which is usually reversible. Therefore, the combination should be administered with caution in patients with compromised renal function.

Acetaminophen

Acetaminophen had no effect on the plasma levels of sulindac or its sulfide metabolite.

Aspirin

The concomitant administration of aspirin with sulindac significantly depressed the plasma levels of the active sulfide metabolite. A double-blind study compared the safety and efficacy of Clinoril (sulindac) 300 or 400 mg daily given alone or with aspirin 2.4 g/day for the treatment of osteoarthritis. The addition of aspirin did not alter the types of clinical or laboratory adverse experiences for Clinoril (sulindac) ; however, the combination showed an increase in the incidence of gastrointestinal adverse experiences. Since the addition of aspirin did not have a favorable effect on the therapeutic response to Clinoril (sulindac) , the combination is not recommended.

Cyclosporine

Administration of non-steroidal anti-inflammatory drugs concomitantly with cyclosporine has been associated with an increase in cyclosporine-induced toxicity, possibly due to decreased synthesis of renal prostacyclin. NSAIDs should be used with caution in patients taking cyclosporine, and renal function should be carefully monitored.

Diflunisal

The concomitant administration of Clinoril (sulindac) and diflunisal in normal volunteers resulted in lowering of the plasma levels of the active sulindac sulfide metabolite by approximately one-third.

Diuretics

Clinical studies, as well as post marketing observations, have shown that Clinoril (sulindac) can reduce the natriuretic effect of furosemide and thiazides in some patients. This response has been attributed to inhibition of renal prostaglandin synthesis. During concomitant therapy with NSAIDs, the patient should be observed closely for signs of renal failure, as well as to assure diuretic efficacy.

DMSO

DMSO should not be used with sulindac. Concomitant administration has been reported to reduce the plasma levels of the active sulfide metabolite and potentially reduce efficacy. In addition, this combination has been reported to cause peripheral neuropathy.

Lithium

NSAIDs have produced an elevation of plasma lithium levels and a reduction in renal lithium clearance. The mean minimum lithium concentration increased 15% and the renal clearance was decreased by approximately 20%. These effects have been attributed to inhibition of renal prostaglandin synthesis by the NSAID. Thus, when NSAIDs and lithium are administered concurrently, subjects should be observed carefully for signs of lithium toxicity.

Methotrexate

NSAIDs have been reported to competitively inhibit methotrexate accumulation in rabbit kidney slices. This may indicate that they could enhance the toxicity of methotrexate. Caution should be used when NSAIDs are administered concomitantly with methotrexate.

NSAIDs

The concomitant use of Clinoril (sulindac) with other NSAIDs is not recommended due to the increased possibility of gastrointestinal toxicity, with little or no increase in efficacy.

Oral anticoagulants

Although sulindac and its sulfide metabolite are highly bound to protein, studies in which Clinoril (sulindac) was given at a dose of 400 mg daily have shown no clinically significant interaction with oral anticoagulants. However, patients should be monitored carefully until it is certain that no change in their anticoagulant dosage is required. Special attention should be paid to patients taking higher doses than those recommended and to patients with renal impairment or other metabolic defects that might increase sulindac blood levels. The effects of warfarin and NSAIDs on GI bleeding are synergistic, such that users of both drugs together have a risk of serious GI bleeding higher than users of either drug alone.

Oral hypoglycemic agents

Although sulindac and its sulfide metabolite are highly bound to protein, studies in which Clinoril (sulindac) was given at a dose of 400 mg daily, have shown no clinically significant interaction with oral hypoglycemic agents. However, patients should be monitored carefully until it is certain that no change in their hypoglycemic dosage is required. Special attention should be paid to patients taking higher doses than those recommended and to patients with renal impairment or other metabolic defects that might increase sulindac blood levels.

Probenecid

Probenecid given concomitantly with sulindac had only a slight effect on plasma sulfide levels, while plasma levels of sulindac and sulfone were increased. Sulindac was shown to produce a modest reduction in the uricosuric action of probenecid, which probably is not significant under most circumstances.

Propoxyphene hydrochloride

Propoxyphene hydrochloride had no effect on the plasma levels of sulindac or its sulfide metabolite.