Valdecoxib (Oral)

As a cyclooxygenase-2 inhibitor, Valdecoxib is distinguished from steroids that have some similar effects and, as such, this nonsteroidal anti-inflammatory drug (NSAID) has a myriad of applications in the treatment of everything from arthritis variations to menstruation complications.

Overview

Valdecoxib is an NSAID that is used as an alternative to steroids as it has similar anti-inflammatory effects. In the past, it was marketed under the brand name Bextra, but, after about four years of sales, the Food and Drug Administration decided to remove it from the United States market due to concerns about some intense complications that involve the cardiovascular system. In the European Union, it is known as Dynastat - a water-soluble and injectable prodrug form of the medication.

Pfizer was the manufacturer of this NSAID, but they removed the product from the market based on the aforementioned concerns. This drug required a prescription from a doctor in order to be acquired, and it came in a tablet form. The proper dose will depend on the patient and should be customized to their particular issues. Doses should not be doubled, but a missed dose should be taken as soon as possible. However, if it is nearing the time for the next dose, then it is best to simply take that next dose without worrying about making up for the gap in coverage.

The drug is available in either tablet form or water-soluble injectable versions. The tablet is a white and film-coated. It can be capsule-shaped with a debossed '10' on one side along with a complementary four-pointed star shape on the other side of the tablet if it is the 10mg Betrox version. There is also a 20mg Betrox version that has a debossed '20' on one of the sides in place of the '10'.

Conditions treated

  • Osteoarthritis
  • Rheumatoid Arthritis
  • Dysmenorrhea - Menstruation Pain
  • Menstrual Symptoms
  • Rheumatism

Type of medicine

  • 10mg or 20mg tablet
  • water-soluble injectable version

Side effects

There is the possibility of quite a number of side effects from Valdecoxib. Some of the most major of these are the cardiovascular (CV) adverse events, as noted by the FDA. If a skin rash related to other NSAIDs is already present, then this drug can exaggerate this already existing condition. An allergy to sulfonamides is also likely to cause exaggerated skin reactions in users of Valdecoxib. Liver toxicity might manifest in some users, with the first signals of this appearing in the form of drowsiness, nausea and stomach pain. Therefore, it is appropriate to consult with a physician if any of these complications begin to be felt or seen.

In another direction, anaphylaxis is a rarer allergic reaction that has a higher chance of appearing in those who already have known issues with aspirin, other NSAIDs, or sulfonamide-type drugs. The onset of anaphylaxis will usually manifest in the form of breathing problems, such as fast or irregular breathing, as well as wheezing and fainting. Any of these side effects will require immediate medical attention so as to prevent irreversible damage.

Some of the less common side effects include the following:

  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • vomiting of blood or material that looks like coffee grounds
  • yellow eyes or skin
  • rapid weight gain
  • severe stomach pain
  • tingling of the hands or feet
  • trouble breathing with exertion
  • bloating or swelling of the face, arms, hands, lower legs, feet
  • blood in urine
  • bloody, black, or sticky stools
  • blurred vision
  • nervousness
  • pale skin
  • pounding in the ears
  • rapid weight gain
  • severe stomach pain
  • decreased or painful urination
  • dizziness
  • fever
  • muscle aches and pains
  • nausea

Dosage

The proper dosage depends on the unique individual, as well as the type of health problems that the medication is being used to treat. The initial dose of this drug, when used with one of the variations of arthritis, is generally best started at 10mg at an interval of once per day. Dysmenorrhea applications are ideally started at about 20mg at an interval of once per day. Valdecoxib can also be used for acute pain, such as before surgery, and, in such a case, the recommended dosage is generally 20mg to 40mg at a space of about an hour to an hour and a half before surgery or when needed.

Drug Interactions

There are an abundance of drugs that have been known to interact with Valdecoxib to various degrees, and it is important that anything taken in the same timeframe is considered by a knowledgeable doctor. This number includes about 45 drugs that cause major complications, along with an additional 402 moderate and 73 minor drug interactions. Some of the most widespread interactions are listed here.

Aspirin

Concomitant administration of aspirin with Valdecoxib has been known to increase the risk of GI ulceration and related complications, as opposed to when Valdecoxib is taken by itself. However, unfortunately, Valdecoxib is not a reliable substitute for aspirin when it comes to things like cardiovascular prophylaxis. This is due to the lack of antiplatelet effect, and so this should be considered when necessary.

ACE-Inhibitors

NSAIDs such as Valdecoxib are known for their lowering of the antihypertensive effect that ACE-inhibitors are often used for. This is a relevant interaction that should be considered when anyone is taking Bextra concomitantly with these other medications.

Furosemide

Furosemide and thiazides are often used for their natriuretic effect, and this can be lessened in some patients when there is the concomitant use of NSAIDs such as Valdecoxib. Research has shown that it is likely the inhibition of renal prostaglandin synthesis that causes this effect.

Anticonvulsants

A number of medications that are known as anticonvulsants in the same manner as Phenytoin, in that they help to prevent seizures, might have an effect on the steady-state plasma exposure (AUC) of Valdecoxib. When administered together, research has shown that something like a 27% decrease has been seen. For that reason, Bextra patients should be closely monitored to see if this type of reaction is occurring within them if they are also on an anticonvulsant like Phenytoin.

Dextromethorphan

DXM is a well-known cough suppressant, and taking it at the same time as Valdecoxib (Bextra) has shown that there is a significant increase in plasma levels of the drug. That is most likely due to the fact that there is a weak inhibition effect of the related 2D6 that is causing this lowering. Ironically, even an increase in levels does not help with this problem, and so adjusting the dosages is not required as that will be mostly ineffective.

Lithium and Warfarin

The lithium serum clearance level reduces when used concomitantly with Valdecoxib. As well as this, the Warfarin anticoagulant effect is also somewhat reduced. Both of these interactions will require more careful monitoring when there is a change in the therapy so that these effects can be made negligible.

Diazepam

Also known as Valium due to its first marketed name, this drug has an increase in its exposure level to the plasma when used in conjunction with Valdecoxib. This occurs at the higher dosage levels such as 40mg. The variations that were noted are likely not significant enough to require any type of dosage adjustments, but there could be an increase in some side effects related to the sedative nature of the drug. Also, it is important to avoid any type of hazardous activities that call for the patient to use a high degree of mental vigilance throughout.

Oral contraceptives

Coadministration with these types of medications, such as Ortho-Novum 1/35, has been seen to increase the exposure of medications such as norethindrone (NET) and ethinyl estradiol quite a bit. There is quite a negligible chance of this causing any interference with the efficacy of the contraceptive, but it should still be taken into consideration as part of the patient consultant they will be used together.

Glyburide

Smaller doses of Valdecoxib in conjunction with Glyburide did not have any effect, but at the 40mg level there were increases in the area under the curve at a rise of 21%, as well as a 16% decrease in the glucose area under the curve (AUC). Anything higher than 40mg has not been taken into consideration through a similar research phase.

Omeprazole

Finally, it may be important to watch for prescribing drugs in conjunction with Omeprazole and Valdecoxib if their absorption rate is sensitive to pH. No dose adjustment is recommended because there has been research showing that even patients with Zollinger-Ellison, or ZE, have been able to tolerate such a combination. As with most of these other drug interactions, there has been no study realized on anything higher than the 40mg option.

Warnings

There is a myriad of various warnings that have been issued for this drug, and, if encountered, they could lead to quite serious complications. It is vital to look at the entire picture when using the drug Valdecoxib, and this is especially true when it is used concomitantly with others.

Gastrointestinal effects

The gastrointestinal tract is very important to the human condition because of the fact that it encompasses everything necessary to take in the food and digest it appropriately through the various organs before expelling it from the body. Nonsteroidal anti-inflammatory drugs have, in general, the potential to cause issues in this GI tract quite immediately and without previous symptoms having manifested. For example, this GI toxicity can lead to bleeding in various areas of the tract, as well as ulceration and perforation. The small intestine, large intestine and stomach can all be affected similarly, and since Valdecoxib is an NSAID itself, it has the potential for problems in the same way.

Any physician who prescribes the drug should be sure to inform their patient of the various signs and symptoms that might be noticed during gastrointestinal complications, so that there can be action as quick as possible in response. Unfortunately, even then, only about one in five who develop a severe adverse reaction in the region will be symptomatic and noticeable. Therefore, it is critical that extreme caution is taken when issuing such a drug to those who have already been known to be prone to gastrointestinal sensitivity. This includes those who have had GI bleeding or ulcer disease.

Skin reactions of high severity

Since Valdecoxib has a sulfonamide moiety, it is wise for patients that have a known history of being allergic to it to take precaution. They are more likely to have severe skin reactions, but it is not a requirement that an allergy history be present in order for these skin reactions to manifest. Here are some of those conditions that might appear:

  • Erythema multiforme
  • Stevens-Johnson syndrome
  • Toxic epidermal necrolysis

Especially during the earliest part of a course of therapy with Valdecoxib, there have been such conditions, with some even leading to death in the patient (Stevens-Johnson complications).

Anaphylactoid reactions

The hypersensitivity reactions that can sometimes occur have been related to a course of therapy with Valdecoxib. Both the anaphylactic reactions and angioedema have shown up in some patients, and, for that reason, it is important that the physicians do not give it to patients with the aspirin triad. Some asthmatic patients are more likely to experience such a reaction.

Coronary artery bypass graft surgery

Due to the greater chance of such things as cardiovascular and thromboembolic events, sternal wound problems and deeper surgical infections, the drug Valdecoxib has been contraindicated from patient pain after CABG surgery.

Other warnings

Also, patients with advanced renal disease should not be given the drug due to the fact that there is no information regarding potential complications there. Likewise, it should not be used in women who are in the late pregnancy stage, due to the fact that the ductus arteriosus could be closed early.

As a selective COX-2 inhibitor, Valdecoxib is in a class with other similar medications, though many have been taken off of the market, due to the complications in patients. Peptic ulceration has been one of the most common of those complications in previous classes of coxibs that includes celecoxib, rofecoxib and other members as well. The coxibs in this class all directly target COX-2, and this has been sought because of the fact that it limits the chance of the peptic ulceration issues from becoming present in the patient.

Storage

The Bextra 10mg and 20mg tablets came in both bottles of 100 and bottles of 500. There were also cartons of 100 dose units, and all of these need to be stored in a dry area at a temperature of 77 degrees Fahrenheit for the most ideal longevity. However, there can be exceptions for taking a dose into areas that are between 59 and 86 degrees.

Summary

Bextra was the brand of Valdecoxib, and it was a tablet that was used to treat the signs and symptoms of osteoarthritis and rheumatoid arthritis. It has also been used on women for the relief of primary dysmenorrhea, that is also known as painful menstruation. The recommended dosage has been set at 10mg and 20mg accordingly. As a nonsteroidal anti-inflammatory drug, it is a COX-2 inhibitor and uses that mechanism to achieve most of its success.

However, in September 2009, Pfizer did end up having to pay the largest health care fraud settlement of all time, due to the fact that the legal system determined that the company had marketed the product with the intent to deceive. A $2.3 billion fine was paid in respect to the Pharmacia and Upjohn subsidiaries of Pfizer, who were the ones who received the brunt of the blame.

Heart attack and strokes have been found to be the most severe of the common side effects, and there have also been some instances of a serious and fatal skin conditions that can occur in patients who are using the drug as well. The version that still is in existence is a prodrug (converted within the body into a pharmacologically active drug) that is injectable and available in the European Union. There it is marketed under the name Dynastat with a real name of Parecoxib.

Anyone who takes this drug or a related version should be aware of the various warnings and drug interactions that have been mentioned above. The assigning physician should take into consideration all of the patient's past history and current conditions so that the proper decision can be made in regards to whether it is an appropriate prescription and dosage determinations. If a course of therapy with Valdecoxib is taken, then the patient and doctor should both monitor the body closely, since some of the symptoms that may manifest are quite hidden, and, in other cases, they may be totally invisible without close medical inspection.

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Last Reviewed:
December 23, 2017
Last Updated:
April 05, 2018
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