Common Side Effects

• According to Drugs.com, most patients who take Celebrex will experience no side effects. But the most common side effects are a stuffy nose, an upset stomach, a sore throat, nausea, heartburn, gas, dizziness, diarrhea and constipation. A doctor's visit is recommended when the symptoms persist.
  
  

When Not to Take It

• Drugs.com recommends that patients should not take Celebrex if they are allergic to the drug's ingredients; have severe allergic reactions to aspirin, other NSAID pain relievers or a sulfomadine; have either recently had or will soon have heart surgery; have severe liver or kidney problems; have three months remaining in a pregnancy; or are taking another NSAID. A visit to the doctor is recommended before beginning treatment.
  
  

Gastrointestinal Effects

• Drugs.com reports that some of the more serious side effects manifest in patients who already suffer from stomach bleeding or ulcers. In fact, half of the drug's reported deaths have been in patients who had those ailments. Eleven other cases of stomach hemorrhage resulted in hospitalization. Still, a celecoxib long-term arthritis safety study (CLASS) showed the cumulative incidence of upper gastrointestinal complicated and symptomatic ulcers among non-aspirin users taking the generic was 0.78 percent after nine months of use.
  
  

Cardiovascular Effects

• The CLASS study showed patients taking Celebrex, low-dose aspirin or diclofenac face severe side effects less that 2 percent of the time in each instance. Drugs.com indicates Celebrex patients face cardiovascular side effects from the drug from 4 percent to 13.4 percent of the time, and those effects can include hypertension, ventricular fibrillation and myocardial infarcion. A National Institute of Health study showed that patients are at a higher risk of these side effects if they have colorectal cancer.
  
  

Hematologic Side Effects

• Drugs.com reports symptoms such as decreased hematocrit, decreased hemoglobin and prolonged activated partial thromboplastin time have presented in up to 13.4 percent of the patients who have taken Celebrex. One man, who also suffered from gout, had a case of deep vein thrombosis. Another man faced acute methemoglobinemia, but the symptoms resolved themselves when he discontinued the medication.
  
  

Hepatic Side Effects

• The general side effects include abnormal liver function tests and increased transaminase, which Drugs.com reports has been seen in 3.9 to 13.4 percent of patients who have taken Celebrex. In rarer cases, the drug results in jaundice, liver failure and hepatitis. Cholestatic hepatitis rarely occurs.
  
  

Renal Side Effects

• The most common renal side effect is blood creatine phosphokinase, which can occur in up to 13.4 percent of patients. Increased creatine can also occur, and acute renal failure is seen in less than 1 percent of patients, according to Drugs.com. One woman with rheumatoid arthritis reported a bout with renal papillary necrosis that stopped after she stopped taking Celebrex.