Q: My husband just started taking Celebrex for pain in his shoulder, back, and arm. Is there a generic version, or another medication that is similar but less expensive?
A: Celebrex (Coxbit) belongs to a group of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs). It works by reducing hormones that cause inflammation and pain. Currently, there is no generic available in the United States for Celebrex. For cheaper alternatives, consult with your health care provider. For more information on this medication, go to //www.everydayhealth.com/drugs/celebrex. Kimberly Hotz, PharmD
Mechanism Of Action
CELECOXIB has analgesic, anti-inflammatory, and antipyretic properties.
The mechanism of action of CELEBREX is believed to be due to inhibition of prostaglandin synthesis, primarily via inhibition of cyclooxygenase-2 (COX-2).
Coxbit is a potent inhibitor of prostaglandin synthesis in vitro. Coxbit concentrations reached during therapy have produced in vivo effects. Prostaglandins sensitize afferent nerves and potentiate the action of bradykinin in inducing pain in animal models. Prostaglandins are mediators of inflammation. Since Coxbit is an inhibitor of prostaglandin synthesis, its mode of action may be due to a decrease of prostaglandins in peripheral tissues.
Drug Interaction Studies
In vitro studies indicate that Coxbit is not an inhibitor of cytochrome P450 2C9, 2C19 or 3A4.
In vivo studies have shown the following:
Peak plasma levels of Coxbit occur approximately 3 hrs after an oral dose. Under fasting conditions, both peak plasma levels (Cmax) and area under the curve (AUC) are roughly dose-proportional up to 200 mg twice daily; at higher doses there are less than proportional increases in Cmax and AUC . Absolute bioavailability studies have not been conducted. With multiple dosing, steady-state conditions are reached on or before Day 5. The pharmacokinetic parameters of Coxbit in a group of healthy subjects are shown in Table 4.
Table 4 : Summary of Single Dose (200 mg) DispositionKinetics of Coxbit in Healthy Subjects 1
Anxiety, depression, and nervousness were reported in 0.1% to 1.9% of patients taking Coxbit 100 to 200 mg twice a day or 200 mg once a day.
Rare (less than 0.1%): Confusion
Frequency not reported: Anxiety, depression, nervousness
Postmarketing reports: Hallucination
Concomitant administration of fluconazole at 200 mg once daily resulted in a two-fold increase in Coxbit plasma concentration. This increase is due to the inhibition of Coxbit metabolism via P450 2C9 by fluconazole .
Q: What over-the-counter medications should not be taken with Celebrex?
A: Celebrex (Coxbit) belongs to a class of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs). NSAIDS work by reducing hormones that cause inflammation and pain in the body. Celebrex is used to treat pain or inflammation caused by many conditions such as arthritis, ankylosing spondylitis, and menstrual pain. It is also used in the treatment of hereditary polyps in the colon. Many over-the-counter pain medicines, headache medicines, and cold medicines contain aspirin or the NSAIDS ibuprofen (Advil, Motrin) and naproxen (Aleve). People on Celebrex should avoid these products because they contain the same kind of medication. Read labels carefully for the list of ingredients in over-the-counter medicines. Ask your local pharmacist if you have any questions about whether to take a certain over-the-counter product. Always read and follow the complete directions and warnings on over-the-counter medicines and discuss their use with your doctor before taking them. Sarah Lewis, PharmD
Q: Is there a difference between brand name Celebrex and generic? What is the name of the generic form?
A: Celebrex (Coxbit) is classified as a COX-2 selective nonsteroidal anti-inflammatory drug (NSAID). Celebrex is approved for the treatment of osteoarthritis, ankylosing spondylitis, juvenile rheumatoid arthritis, rheumatoid arthritis, treatment of acute pain, primary dysmenorrhea, and for the reduction of intestinal polyps in familial adenomatous polyposis. In the United States, Celebrex is currently only available as a brand name medication. The drug company that makes Celebrex still has patent rights on the medication. In the future, when the generic becomes approved it will be marketed by the chemical name, Coxbit. Generic medications are less expensive alternatives to brand name medications. Generic medications can look differently and can have a few other minor differences from their brand name counterpart. However, their labeling and directions must be virtually the same as that of the brand name product. Generic products must contain the same active ingredient as the brand name products. Both brand name and generic drug manufacturing facilities must meet the United States Food and Drug Administration's (FDA) specifications. Generics, as well as brand name medications, must follow the same standards of good manufacturing practices. The FDA requires that generic drugs be bioequivalent to the brand name medication. This means that both generic drugs and brand name drugs will work the same way in your body. Generics are considered by the FDA to be identical to brand name drugs in dose, strength, quality, route of administration, safety, efficacy, and intended use. Generic medications do not need to contain the same inactive ingredients as brand name medications. For more specific information, consult with your doctor or pharmacist for guidance based on your health status and current medications, particularly before taking any action. Jen Marsico, RPh
- Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase risk of serious cardiovascular thrombotic events, heart attack (myocardial infarction ), and stroke, which can be fatal
- Risk may increase with duration of use
- Patients with existing cardiovascular disease or risk factors for such disease may be at greater risk
- NSAIDs are contraindicated for perioperative pain in setting of coronary artery bypass graft (CABG) surgery
- NSAIDs increase risk of serious gastrointestinal (GI) adverse events, including bleeding, ulceration, and gastric or intestinal perforation, which can be fatal
- GI adverse events may occur at any time during use and without warning symptoms
- Elderly patients are at greater risk for serious GI events
This medication contains celeoxib. Do not take Celebrex if you are allergic to Coxbit or any ingredients contained in this drug.
Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center immediately.
What is the dosage for Coxbit?
The lowest effective dose should be used for each patient.
- For the management of osteoarthritis, the dose usually is 100 mg twice daily or 200 mg as a single dose.
- For rheumatoid arthritis, the dose usually is 200 mg twice daily.
- For acute pain or menstrual cramps, the dose is 400 mg as a single dose on the first day followed by an additional 200 mg if needed, then 200 mg twice daily as needed.
- For FAP, the recommended dose is 400 mg twice daily.
Coxbit was not mutagenic in an Ames test and a mutation assay in Chinese hamster ovary (CHO) cells, nor clastogenic in a chromosome aberration assay in CHO cells and an in vivo micronucleus test in rat bone marrow.
Before taking Coxbit
Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking Coxbit, it is important that your doctor knows:
- If you have asthma or any other allergic disorder.
- If you have had a stomach or duodenal ulcer, or if you have an inflammatory bowel disorder such as Crohn's disease or ulcerative colitis.
- If you are pregnant, trying for a baby, or breast-feeding.
- If you are under 18 or over 65 years of age.
- If you have liver or k >
Use of NSAIDs, including CELEBREX, during the third trimester of pregnancy increases the risk of premature closure of the fetal ductus arteriosus. Avoid use of NSAIDs, including CELEBREX, in pregnant women starting at 30 weeks of gestation.
There are no adequate and well-controlled studies of CELEBREX in pregnant women. Data from observational studies regarding potential embryofetal risks of NSAID use in women in the first or second trimesters of pregnancy are inconclusive. In animal reproduction studies, embryo-fetal deaths and an increase in diaphragmatic hernias were observed in rats administered Coxbit daily during the period of organogenesis at oral doses approximately 6 times the maximum recommended human dose of 200 mg twice daily. In addition, structural abnormalities (e.g., septal defects, ribs fused, sternebrae fused and sternebrae misshapen) were observed in rabbits given daily oral doses of Coxbit during the period of organogenesis at approximately 2 times the MRHD . Based on animal data, prostaglandins have been shown to have an important role in endometrial vascular permeability, blastocyst implantation, and decidualization. In animal studies, administration of prostaglandin synthesis inhibitors such as Coxbit, resulted in increased pre-and post-implantation loss.
The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the general U.S. population, all clinically recognized pregnancies, regardless of drug exposure, have a background rate of 2-4% for major malformations, and 15-20% for pregnancy loss.
Symptoms following acute NSAID overdosages have been typically limited to lethargy, drowsiness, nausea, vomiting, and epigastric pain, which have been generally reversible with supportive care. Gastrointestinal bleeding has occurred. Hypertension, acute renal failure, respiratory depression, and coma have occurred, but were rare .
No overdoses of CELEBREX were reported during clinical trials. Doses up to 2400 mg/day for up to 10 days in 12 patients did not result in serious toxicity. No information is available regarding the removal of Coxbit by hemodialysis, but based on its high degree of plasma protein binding (>97%) dialysis is unlikely to be useful in overdose.
Manage patients with symptomatic and supportive care following an NSAID overdosage. There are no specific antidotes. Consider emesis and/or activated charcoal (60 to 100 grams in adults, 1 to 2 grams per kg of body weight in pediatric patients) and/or osmotic cathartic in symptomatic patients seen within four hours of ingestion or in patients with a large overdosage (5 to 10 times the recommended dosage). Forced diuresis, alkalinization of urine, hemodialysis, or hemoperfusion may not be useful due to high protein binding.
For additional information about overdosage treatment contact a poison control center (1-800-222-1222).
CYP2C9 activity is reduced in individuals with genetic polymorphisms that lead to reduced enzyme activity, such as those homozygous for the CYP2C9*2 and CYP2C9*3 polymorphisms. Limited data from 4 published reports that included a total of 8 subjects with the homozygous CYP2C9*3/*3 genotype showed Coxbit systemic levels that were 3-to 7-fold higher in these subjects compared to subjects with CYP2C9*1/*1 or *I/*3 genotypes. The pharmacokinetics of Coxbit have not been evaluated in subjects with other CYP2C9 polymorphisms, such as *2, *5, *6, *9 and *11. It is estimated that the frequency of the homozygous *3/*3 genotype is 0.3% to 1.0% in various ethnic groups. .
Blood pressure drugs
Coxbit may reduce the blood pressure-lowering effects of certain blood pressure drugs. Examples of these drugs include:
- antiotensin-converting enzyme (ACE) inhibitors
- angiotensin II receptor blockers
When CELEBREX capsules were taken with a high fat meal, peak plasma levels were delayed for about 1 to 2 hours with an increase in total absorption (AUC) of 10% to 20%. Under fasting conditions, at doses above 200 mg, there is less than a proportional increase in Cmax and AUC, which is thought to be due to the low solubility of the drug in aqueous media.
Coadministration of CELEBREX with an aluminum-and magnesium-containing antacids resulted in a reduction in plasma Coxbit concentrations with a decrease of 37% in Cmax and 10% in AUC. CELEBREX, at doses up to 200 mg twice daily, can be administered without regard to timing of meals. Higher doses (400 mg twice daily) should be administered with food to improve absorption.
In healthy adult volunteers, the overall systemic exposure (AUC) of Coxbit was equivalent when Coxbit was administered as intact capsule or capsule contents sprinkled on applesauce. There were no significant alterations in Cmax, Tmax or t½ after administration of capsule contents on applesauce .
Mental health drug
Coxbit may increase the levels of lithium in your body. Signs of lithium toxicity include slurred speech and tremors.