Dexamethasone with edema of the brain
Synthetic fluorinated GCS with pronouncedanti-inflammatory, anti-allergic, immunosuppressive. It inhibits the release of ACTH, slightly affects the level of blood pressure and water-salt metabolism. 35 times more active than cortisone and 7 times more active than prednisolone. It induces the synthesis and secretion of lipomodulin inhibiting phospholipase A2, inhibits the formation of metabolites of arachidonic acid, interferes with the interaction of IgE with the receptors of mast cells and basophilic granulocytes and activates the complement system, reduces the exudation and permeability of capillaries. Immunodepressive effect is due to inhibition of the release of lymphocytic and macrophage cytokines. It affects the catabolism of proteins, stimulates gluconeogenesis in the liver and reduces the utilization of glucose in peripheral tissues, suppresses the activity of vitamin D, which leads to a violation of calcium absorption and more active excretion. Suppresses the synthesis and secretion of ACTH and again ?? synthesis of endogenous GCS. In contrast to prednisolone does not have mineralocorticoid activity; inhibits the function of the pituitary gland.
After ingestion quickly and completelyabsorbed in the digestive tract. The maximum concentration in the blood plasma is reached after 1 ?? 2 hours. About 60% of the active substance binds to plasma albumins. The half-life? more than 5 hours. It is actively metabolized in many tissues, especially in the liver under the action of cytochrome-containing CYP 2C enzymes, and is excreted in the form of metabolites with feces and urine. The half-life is an average of 3 hours. In severe liver diseases, during pregnancy, while taking oral contraceptives, the half-life of dexamethasone increases.
After instillation into the conjunctival sacDexamethasone penetrates well into the epithelium of the cornea and conjunctiva; therapeutic concentrations are achieved in the aqueous humor of the eye. The duration of anti-inflammatory action after instillation in the eye 1 drop of 0.1% of p-ra or suspension 4 ?? 8 h.
A cerebral edema caused by a tumor,a brain injury, cerebral hemorrhage, encephalitis, or meningitis; progressive rheumatoid arthritis in the period of exacerbation; BA; acute erythroderma, pemphigus, initial treatment of acute eczema; sarcoidosis; nonspecific ulcerative colitis; severe infectious diseases (in combination with antibiotics or other chemotherapeutic agents); palliative therapy of a malignant tumor. They are also used for replacement therapy with severe adrenogenital syndrome.
Periarticular infiltration therapyspend with periarthritis, epicondylitis, bursitis, tenosynovitis, intra-articular injection ?? with arthritis of non-microbial etiology; in ophthalmology ?? in the form of subconjunctival injections in inflammatory diseases of the eyes (after injuries and surgical interventions).
Eye drops ?? scleritis, episcleritis, iritis, optic neuritis, sympathetic ophthalmia, conditions after injuries and ophthalmic operations.
Inside, injected in / in and / m, intra- and periarticular, subconjunctival, used in the form of eye drops.
With edema of the brain with a heavy courseTreatment usually begins with iv injection of dexamethasone, when the condition improves, they switch to ingestion 4-16 mg / day. With an easier flow is appointed orally, usually 2-8 mg dexamethasone per day.
With rheumatoid arthritis during an exacerbation, asthma,in the acute course of skin diseases, sarcoidosis and acute ulcerative colitis treatment is started with a dose of 4-16 mg / day. With the planned long-term therapy after elimination of acute symptoms of the disease, dexamethasone should be replaced with prednisone or prednisolone.
In severe infectious diseases (in combination with antibiotics and other chemotherapeutic agents), 8-16 mg dexamethasone per day is administered for 2 to 3 days with a rapid dose reduction.
With palliative therapy of a malignant tumor, the initial dose of dexamethasone is 8-16 mg / day; at long treatment ?? 4 ?? 12 mg / day.
Adolescents and adults with congenital adrenogenital syndrome are prescribed 1 mg / day, if necessary, additionally prescribed mineralocorticoids.
Dexamethasone is administered internally after a meal,preferably after breakfast, with a small amount of liquid. The daily dose should be taken once in the morning (circadian therapy regimen). In the treatment of cerebral edema, as well as in the conduct of palliative therapy, it may be necessary to divide the daily dose by 2 to 4 doses. After achieving a satisfactory therapeutic effect, the dose should be reduced to a minimally effective maintenance dose. To complete the course of treatment, this dose continues to be gradually reduced to restore the function of the adrenal cortex.
With a local infiltration, 4 to 8 mg is prescribed, with intra-articular insertion into small joints? 2 mg; with subconjunctival ?? 2 ?? 4 mg.
Eye drops (0.1%) are applied at a dose of 1? 2 drops inthe beginning of treatment every 1 ?? 2 hours, then, with a decrease in the severity of inflammatory phenomena ?? every 4 ?? 6 hours. Duration of treatment ?? from 1 ?? 2 days to several weeks, depending on the effect obtained.
For long-term use of dexamethasone, excepturgent and substitution therapy, contraindications are peptic ulcer of the stomach and duodenum, severe forms of osteoporosis. mental illness in the anamnesis, shingles, rosacea, chicken pox, a period of 8 weeks before and 2 weeks after vaccination, lymphadenitis after a prophylactic vaccination against tuberculosis. amoebic infections, systemic mycoses, poliomyelitis (with the exception of the bulbar-encephalitic form), closed-angle and open-angle glaucoma. For the use of eye drops contraindications are treelike herpetic keratitis, acute phases of vaccination, chicken pox and other infectious lesions of the cornea and conjunctiva, tuberculosis of the eyes and fungal infections.
With prolonged (more than 2 weeks) treatment is possibledevelopment of functional insufficiency of the adrenal cortex, sometimes note obesity, muscle weakness, increased blood pressure, osteoporosis. hyperglycemia (decreased glucose tolerance), diabetes mellitus, violation of the secretion of sex hormones (amenorrhoea, hirsutism, impotence), the moonlike face, the appearance of striae, petechiae, ecchymosis, steroid acne; there may be a delay in sodium with edema, increased potassium secretion, atrophy of the adrenal cortex, vasculitis (including as a manifestation of withdrawal syndrome after prolonged therapy), epigastric pain, peptic ulcer of the stomach, immunosuppression, increased risk of infection, thrombosis; delayed healing of wounds, growth in children, aseptic necrosis of the bones (head of the femoral and humerus), glaucoma, cataract, mental disorders, pancreatitis. When using eye drops ?? glaucoma with optic nerve damage, violation of acuity and visual fields, the formation of subcapsular cataracts, secondary eye infections, including simple herpes, corneal integrity, rarely ?? acute pain or burning sensation after instillation.
Use in severe infections is possible onlyin combination with etiological therapy. When specifying a history of tuberculosis, dexamethasone should be used only with the simultaneous prophylactic appointment of a patient with anti-tuberculosis drugs.
During pregnancy,strict indications; with prolonged therapy, it is possible that the fetus is prenatal. In the case of dexamethasone at the end of the pregnancy period, there is a risk of atrophy of the adrenal cortex in the fetus, which may necessitate replacement therapy with a gradual decrease in the dose of dexamethasone.
GCS penetrates into breast milk. If you need long-term treatment or the use of dexamethasone in high doses, it is recommended to stop breastfeeding.
Viral diseases in patients receivingdexamethasone, can occur especially hard, especially in children with immunodeficiency states, as well as in individuals who have not previously had measles or chicken pox. If these people during the treatment with dexamethasone are in contact with sick measles or chickenpox, they should be prescribed preventive treatment.
Special situations that occur during treatment with dexamethasone (fever, injuries and surgeries) may require an increase in its dose.
Dexamethasone enhances the effects of cardiacglycosides due to a deficiency of potassium. Simultaneous use with saluretics leads to increased release of potassium. Dexamethasone weakens the hypoglycemic effect of antidiabetic agents and the anticoagulant effect of coumarin derivatives. Rifampicin. phenytoin. Barbiturates weaken the action of GCS. With the simultaneous use of GCS with NSAIDs, the risk of gastropathy increases. Estrogen-containing oral contraceptives enhance the effects of GCS. With a simultaneous appointment with prazikvantelom possible decrease in the concentration of the latter in the blood. ACE inhibitors, when used concomitantly with dexamethasone, sometimes alter the composition of peripheral blood. Chloroquine, hydroxychloroquine. mefloquine in combination with dexamethasone may increase the risk of myopathy, cardiomyopathy. Dexamethasone reduces the effectiveness of somatropin for prolonged use. When combined with the use of protivoelin decreases the level of TSH in the blood.
There is no specific antidote. Dexamethasone should be withdrawn and symptomatic therapy prescribed.