Dexamethasone is a type of steroid medication. It has anti-inflammatory and immunosuppressant effects. It is 25 times more potent than cortisol in its glucocorticoid effect, while having minimal mineralocorticoid effect.
Dexamethasone is used for the treatment of many conditions including: rheumatologic problems, a number of skin diseases such aserythema multiforme, severe allergies, asthma, chronic obstructive lung disease, croup, and cerebral edema, in addition to other medications in tuberculosis and a number of other infectious diseases.[1]
It is pregnancy category C in the United States and class A in Australia, meaning it has been frequently used in pregnancy and not been found to cause problems for the baby.[1][2]
It is on the WHO Model List of Essential Medicines, the most important medications needed in a basic health system.[3]
Medical use[edit]
Anti-inflammatory[edit]
Dexamethasone is used to treat many inflammatory and autoimmune conditions, such as rheumatoid arthritis and bronchospasm.[4]Idiopathic thrombocytopenic purpura, a decrease in numbers of platelets due to an immune problem, responds to 40 mg daily for four days; it may be administered in 14-day cycles. It is unclear whether dexamethasone in this condition is significantly better than other glucocorticoids.[5]
It is also given in small amounts[6] before and/or after some forms of dental surgery, such as the extraction of the wisdom teeth, an operation which often leaves the patient with puffy, swollen cheeks.
It is injected into the heel when treating plantar fasciitis, sometimes in conjunction with triamcinolone acetonide.
It is useful to counteract allergic anaphylactic shock, if given in high doses.
It is present in certain eye drops – particularly after eye surgery – and as a nasal spray (trade name Dexacort), and certain ear drops (Sofradex, when combined with an antibiotic and an antifungal).
Dexamethasone is used in transvenous screw-in cardiac pacing leads to minimize the inflammatory response of the myocardium. The steroid is released into the myocardium as soon as the screw is extended and can play a significant role in minimizing the acute pacing threshold due to the reduction of inflammatory response. The typical quantity present in a lead tip is less than 1.0 mg.
Dexamethasone is often administered before antibiotics in cases of bacterial meningitis. It then acts to reduce the inflammatory response of the body to the bacteria killed by the antibiotics (bacterial death releases proinflammatory mediators that can cause a response which is harmful to the patient), thus improving prognosis and outcome.[7]
Cancer patients undergoing chemotherapy are given dexamethasone to counteract certain side effects of their antitumor treatments. Dexamethasone can augment the antiemetic effect of 5-HT3 receptor antagonists, such as ondansetron.Cancer[edit]
In brain tumors (primary or metastatic), dexamethasone is used to counteract the development of edema, which could eventually compress other brain structures. It is also given in cord compression, where a tumor is compressing the spinal cord.
Dexamethasone is also used as a direct chemotherapeutic agent in certain haematological malignancies, especially in the treatment of multiple myeloma, in which dexamethasone is given alone or in combination with other chemotherapeutic drugs, including most commonly with thalidomide (Thal-dex), lenalidomide, bortezomib (Velcade, Vel-dex),[8] or a combination of adriamycin (doxorubicin) andvincristine or velcade/revlimid/dexamethasone.
Endocrine[edit]
In adrenal insufficiency and Addison's disease, dexamethasone is prescribed when the patient does not respond well to prednisone ormethylprednisolone.
It can be used in congenital adrenal hyperplasia in older adolescents and adults to suppress ACTH production. It is typically given at night.[11]
Pregnancy[edit]
Dexamethasone may be given to women at risk of delivering prematurely to promote maturation of the fetus' lungs. This has been associated with low birth weight, although not with increased rates of neonatal death.[12]
High-altitude illnesses[edit]
Dexamethasone is used in the treatment of high-altitude cerebral edema, as well as pulmonary edema. It is commonly carried on mountain-climbing expeditions to help climbers deal with altitude sickness.[13][14]
Other[edit]
Dexamethasone has been used as an off-label prenatal treatment for the symptoms of congenital adrenal hyperplasia (CAH) in female fetuses. CAH causes a variety of physical abnormalities, notably ambiguous genitalia in girls. Early prenatal CAH treatment has been shown to reduce some CAH symptoms, but it does not treat the underlying congenital disorder.
A small clinical trial found long-term effects on verbal working memory among the small group of children treated prenatally, but the small number of test subjects means the study cannot be considered definitive.[15][16] Administration of prenatal dexamethasone has been the subject of controversy over issues of informed consent and because treatment must predate a clinical diagnosis of CAH in the female fetus.
Synergism[edit]
Dexamethasone and ondansetron are more effective than ondansetron alone in preventing postoperative nausea and vomiting.[17]
Adverse effects[edit]
The exact incidence of the adverse effects of dexamethasone are not available, hence estimates have been made as to the incidence of the adverse effects below based on the adverse effects of related corticosteroids and on available documentation on dexamethasone.
No comments:
Post a Comment