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From: Brian Symonds <[log in to unmask]> Generally speaking, low blood pressure is harder to treat than high blood pressure. Unlike high blood pressure, low blood pressure is not a disease process on its own, but rather is usually due to some process, and the treatment of the low blood pressure becomes the treatment of the process causing it. For example, if you have an infection and it causes your blood pressure to be low, the treatment is to treat the infection. If you are on a medication and it causes your blood pressure to be low, then the treatment is to stop the medication. There are some things that can be done to "support" a person's blood pressure while you are waiting for treatment to become effective. For example, getting extra fluid into the body (either by IV or mouth) will help raise a person's blood pressure, and if the fluid is leaking out of the person's arteries into the tissues, giving protein into the blood (such as albumin) will help hold the fluid in the arteries. However, there also may be adverse consequences to giving extra fluids and proteins (or other such substances). PD patients may get undesirable leg and foot swelling with extra fluids for example. Also low blood pressure with some medications may be unpredictable, and not preventable. For example, orthostatic hypotension (low blood pressure with change in postion) with or without syncope (fainting) can occur with Clozaril (clozapine) treatment and may represent a continuing risk in some patients. Rarely (approximately 1 case per 3,000 patients), collapse can be profound and be accompanied by respiratory and/or cardiac arrest. Orthostatic hypotension is more likely to occur during initial titration in association with rapid dose escalation and may even occur on first dose. In one report, initial doses as low as 12.5 mg were associated with collapse and respiratory arrest. Low blood pressure to the point of collapse is a rare complication with Clozaril and other drugs, but can happen even with a first dose, and is thus not predictable or currently preventable. Benefit must always be balanced against risk. There are drugs used to treat low blood pressure. The main group of medications are called sympathomimetic agents.The sympathomimetic agents (except isoproterenol) are indicated for the correction of hypotension, unresponsive to adequate fluid volume replacement, as part of shock syndrome caused by myocardial infarction, trauma, bacteremia, open-heart surgery, renal failure, chronic cardiac decompensation, drug overdose, or other major systemic illness. Vasopressors such as Dopamine, Dobutamine, Ephedrine, Epinephrine or Adrenalin, Norepinephrine or Noradrenalin, Mephentermine, Metaraminol, Methoxamine, and Phenylephrine are all used in some circumstances to help raise blood pressure, but their usefulness is limited by the fact that some of these can only be given intraveneously, by the fact that they may constrict the arteries in the kidneys and decrease kidney function, by the fact that they can increase the work that the heart has to do, and the fact that they can cause the heart to beat irregularly. They are thus difficult medications to use, and are generally only used for short periods of time till the problem causing the low blood pressure is corrected. What can be done in the situation where a person has low blood pressure due to a disease or medication, and the disease can't be cured, or the medication can't be stopped? The only medication that I am aware of that is currently in use in this situation is Fludrocortisone, and following is information about it. As always, do not be dismayed by the impressive list of potential adverse effects. Used carefully, it is a fairly safe drug, but its potential benefit and its potential harm must always be carefully weighed. FLUDROCORTISONE ACETATE Category/Indications Category: Corticosteroid (mineralocorticoid); antihypotensive (idiopathic orthostatic); diagnostic aid (renal tubular acidosis). Indications: Accepted Adrenocortical insufficiency, chronic primary (treatment); or Adrenocortical insufficiency, chronic secondary (treatment) - Fludrocortisone is indicated as partial replacement therapy in the treatment of adrenocortical insufficiency. Adrenogenital syndrome, congenital (treatment) - Fludrocortisone is indicated in salt-losing forms of adrenogenital syndrome. Hypotension, idiopathic orthostatic (treatment)(1) - Fludrocortisone is used in conjunction with increased sodium intake in the treatment of idiopathic orthostatic hypotension. [Acidosis, in renal tubular disorders (diagnosis and treatment)](1) - Fludrocortisone is used in the treatment of Type IV renal tubular acidosis associated with hyporeninemic hypoaldosteronism. Fludrocortisone is also used as an aid in diagnosing the cause of the condition. Effectiveness of fludrocortisone therapy indicates that the condition is caused by hyporeninemic hypoaldosteronism rather than by renal tubular transport dysfunction. (1)Not included in Canadian product labeling. BRAND NAMES: Astonin*; Florinef * Foreign brand name outside U.S. FORMULARIES: Aetna; BC/BS; Medi-Cal; PCS; WHO DESCRIPTION Fludrocortisone Acetate Tablets USP contain fludrocortisone acetate, a synthetic adrenocortical steroid possessing very potent mineralocorticoid properties and high glucocorticoid activity; it is used only for its mineralocorticoid effects. The chemical name for fludrocortisone acetate is 9-fluoro-11(beta),17,21-trihydroxypregn-4-ene-3, 20-dione 21-acetate. Fludrocortisone Acetate is available for oral administration as scored tablets providing 0.1 mg fludrocortisone acetate per tablet. Inactive ingredients: calcium phosphate, color additive (D&C Red No. 27), corn starch, lactose, magnesium stearate, sodium benzoate, and talc. CLINICAL PHARMACOLOGY The physiologic action of fludrocortisone acetate is similar to that of hydrocortisone. However, the effects of fludrocortisone acetate, particularly on electrolyte balance, but also on carbohydrate metabolism, are considerably heightened and prolonged. Mineralocorticoids act on the distal tubules of the kidney to enhance the reabsorption of sodium ions from the tubular fluid into the plasma; they increase the urinary excretion of both potassium and hydrogen ions. The consequence of these three primary effects together with similar actions on cation transport in other tissues appear to account for the entire spectrum of physiological activities that are characteristic of mineralocorticoids. In small oral doses, fludrocortisone acetate produces marked sodium retention and increased urinary potassium excretion. It also causes a rise in blood pressure, apparently because of these effects on electrolyte levels. In larger doses , fludrocortisone acetate inhibits endogenous adrenal cortical secretion, thymic activity, and pituitary corticotropin excretion; promotes the deposition of liver glycogen; and, unless protein intake is adequate, induces negative nitrogen balance. The approximate plasma half-life of fludrocortisone (fluorohydrocortisone) is 3.5 hours or more and the biological half-life is 18 to 36 hours. CONTRAINDICATIONS Corticosteroids are contraindicated in patients with systemic fungal infections and in those with a history of possible or known hypersensitivity to these agents. WARNINGS BECAUSE OF ITS MARKED EFFECT ON SODIUM RETENTION, THE USE OF FLUDROCORTISONE ACETATE IN THE TREATMENT OF CONDITIONS OTHER THAN THOSE INDICATED HEREIN IS NOT ADVISED. Corticosteroids may mask some signs of infection, and new infections may appear during their use. There may be decreased resistance and inability to localize infection when corticosteroids are used. If an infection occurs during fludrocortisone acetate therapy, it should be promptly controlled by suitable antimicrobial therapy. Prolonged use of corticosteroids may produce posterior subcapsular cataracts, glaucoma with possible damage to the optic nerves, and may enhance the establishment of secondary ocular infections due to fungi or viruses. Average and large doses of hydrocortisone or cortisone can cause elevation of blood pressure, salt and water retention, and increased excretion of potassium. These effects are less likely to occur with the synthetic derivatives except when used in large doses. However, since fludrocortisone acetate is a potent mineralocorticoid, both the dosage and salt intake should be carefully monitored in order to avoid the development of hypertension, edema, or weight gain. Periodic checking of serum electrolyte levels is advisable during prolonged therapy; dietary salt restriction and potassium supplementation may be necessary. All corticosteroids increase calcium excretion. Patients should not be vaccinated against smallpox while on corticosteroid therapy. Other immunization procedures should not be undertaken in patients who are on corticosteroids, especially on high dose, because of possible hazards of neurological complications and a lack of antibody response. The use of Fludrocortisone Acetate Tablets in active tuberculosis should be restricted to those cases of fulminating or disseminated tuberculosis in which the corticosteroid is used for the management of the disease in conjunction with an appropriate antituberculous regimen. If corticosteroids are indicated in patients with latent tuberculosis or tuberculin reactivity, close observation is necessary since reactivation of the disease may occur. During prolonged corticosteroid therapy these patients should receive chemoprophylaxis. PRECAUTIONS General Adverse reactions to corticosteroids may be produced by too rapid withdrawal or by continued use of large doses. To avoid drug-induced adrenal insufficiency, supportive dosage may be required in times of stress (such as trauma, surgery, or severe illness) both during treatment with fludrocortisone acetate and for a year afterwards. There is an enhanced corticosteroid effect in patients with hypothyroidism and in those with cirrhosis. Corticosteroids should be used cautiously in patients with ocular herpes simplex because of possible corneal perforation. The lowest possible dose of corticosteroid should be used to control the condition being treated. A gradual reduction in dosage should be made when possible. Psychic derangements may appear when corticosteroids are used. These may range from euphoria, insomnia, mood swings, personality changes, and severe depression to frank psychotic manifestations. Existing emotional instability or psychotic tendencies may also be aggravated by corticosteroids. Aspirin should be used cautiously in conjunction with corticosteroids in patients with hypoprothrombinemia. Corticosteroids should be used with caution in patients with nonspecific ulcerative colitis if there is a probability of impending perforation, abscess or other pyrogenic infection. Corticosteroids should also be used cautiously in patients with diverticulitis, fresh intestinal anastomoses, active or latent peptic ulcer, renal insufficiency, hypertension, osteoporosis, and myasthenia gravis. Information for Patients The physician should advise the patient to report any medical history of heart disease, high blood pressure, or kidney or liver disease and to report current use of any medicines to determine if these medicines might interact adversely with fludrocortisone acetate (see DRUG INTERACTIONS). Patients who are on immunosuppressant doses of corticosteroids should be warned to avoid exposure to chicken pox or measles, and, if exposed, to obtain medical advice. The patient's understanding of his steroid-dependent status and increased dosage requirement under widely variable conditions of stress is vital. Advise the patient to carry medical identification indicating his dependence on steroid medication and, if necessary, instruct him to carry an adequate supply of medication for use in emergencies. Stress to the patient the importance of regular follow-up visits to check his progress and the need to promptly notify the physician of dizziness, severe or continuing headaches, swelling of feet or lower legs, or unusual weight gain. Advise the patient to use the medicine only as directed, to take a missed dose as soon as possible, unless it is almost time for the next dose, and not to double the next dose. Inform the patient to keep this medication and all drugs out of the reach of children. Laboratory Tests Patients should be monitored regularly for blood pressure determinations and serum electrolyte determinations (see WARNINGS). Drug/Laboratory Test Interactions Corticosteroids may affect the nitrobluetetrazolium test for bacterial infection and produce false-negative results. Carcinogenesis, Mutagenesis, Impairment of Fertility Adequate studies have not been performed in animals to determine whether fludrocortisone acetate has carcinogenic or mutagenic activity or whether it affects fertility in males or females. Pregnancy Category C. Adequate animal reproduction studies have not been conducted with fludrocortisone acetate. However, many corticosteroids have been shown to be teratogenic in laboratory animals at low doses. Teratogenicity of these agents in man has not been demonstrated. It is not known whether fludrocortisone acetate can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Fludrocortisone acetate should be given to a pregnant woman only if clearly needed. Pregnancy. Nonteratogenic Effects. Infants born of mothers who have received substantial doses of fludrocortisone acetate during pregnancy should be carefully observed for signs of hypoadrenalism. Maternal treatment with corticosteroids should be carefully documented in the infant's medical records to assist in follow up. Nursing Mothers Corticosteroids are found in the breast milk of lactating women receiving systemic therapy with these agents. Caution should be exercised when fludrocortisone acetate is administered to a nursing woman. Pediatric Use Safety and effectiveness in children have not been established. Growth and development of infants and children on prolonged corticosteroid therapy should be carefully observed. DRUG INTERACTIONS When administered concurrently, the following drugs may interact with adrenal corticosteroids. Amphotericin B or potassium-depleting diuretics (benzothiadiazines and related drugs, ethacrynic acid and furosemide)--enhanced hypokalemia. Check serum potassium levels at frequent intervals; use potassium supplements if necessary (see WARNINGS). Digitalis glycosides--enhanced possibility of arrhythmias of digitalis toxicity associated with hypokalemia. Monitor serum potassium levels; use potassium supplements if necessary. Oral anticoagulants--decreased prothrombin time response. Monitor prothrombin levels and adjust anticoagulant dosage accordingly. Antidiabetic drugs (oral agents and insulin)--diminished antidiabetic effect. Monitor for symptoms of hyperglycemia; adjust dosage of antidiabetic drug upward if necessary. Aspirin--increased ulcerogenic effect; decreased pharmacologic effect of aspirin. Rarely salicylate toxicity may occur in patients who discontinue steroids after concurrent high-dose aspirin therapy. Monitor salicylate levels or the therapeutic effect for which aspirin is given; adjust salicylate dosage accordingly if effect is altered (see PRECAUTIONS, General). Barbiturates, phenytoin, or rifampin--increased metabolic clearance of fludrocortisone acetate because of the induction of hepatic enzymes. Observe the patient for possible diminished effect of steroid and increase the steroid dosage accordingly. Anabolic steroids (particularly C-17 alkylated androgens such as oxymetholone, methandrostenolone, norethandrolone, and similar compounds)--enhanced tendency toward edema. Use caution when giving these drugs together, especially in patients with hepatic or cardiac disease. Vaccines--neurological complications and lack of antibody response (see WARNINGS). Estrogen--increased levels of corticosteroid-binding globulin, thereby increasing the bound (inactive) fraction; this effect is at least balanced by decreased metabolism of corticosteroids. When estrogen therapy is initiated, a reduction in corticosteroid dosage may be required, and increased amounts may be required when estrogen is terminated. ADVERSE REACTIONS Most adverse reactions are caused by the drug's mineralocorticoid activity (retention of sodium and water) and include hypertension, edema, cardiac enlargement, congestive heart failure, potassium loss, and hypokalemic alkalosis. When fludrocortisone is used in the small dosages recommended, the glucocorticoid side effects often seen with cortisone and its derivatives are not usually a problem; however the following untoward effects should be kept in mind, particularly when fludrocortisone is used over a prolonged period of time or in conjunction with cortisone or a similar glucocorticoid. Musculoskeletal--muscle weakness, steroid myopathy, loss of muscle mass, osteoporosis, vertebral compression fractures, aseptic necrosis of femoral and humeral heads, pathologic fracture of long bones, and spontaneous fractures. Gastrointestinal--peptic ulcer with possible perforation and hemorrhage, pancreatitis, abdominal distention, and ulcerative esophagitis. Dermatologic--impaired wound healing, thin fragile skin, bruising, petechiae and ecchymoses, facial erythema, increased sweating, subcutaneous fat atrophy, purpura, striae, hyperpigmentation of the skin and nails, hirsutism, acneiform eruptions, and hives and/or allergic skin rash; reactions to skin tests may be suppressed. Neurological--convulsions, increased intracranial pressure with papilledema (pseudotumor cerebri) usually after treatment, vertigo, headache, and severe mental disturbances. Endocrine--menstrual irregularities; development of the cushingoid state; suppression of growth in children; secondary adrenocortical and pituitary unresponsiveness, particularly in times of stress (e.g., trauma, surgery, or illness); decreased carbohydrate tolerance; manifestations of latent diabetes mellitus; and increased requirements for insulin or oral hypoglycemic agents in diabetics. Ophthalmic--posterior subcapsular cataracts, increased intraocular pressure, glaucoma, and exophthalmos. Metabolic--hyperglycemia, glycosuria, and negative nitrogen balance due to protein catabolism. Other adverse reactions that may occur following the administration of a corticosteroid are necrotizing angitis, thrombophlebitis, aggravation or masking of infections, insomnia, syncopal episodes, and anaphylactoid reactions. OVERDOSAGE Development of hypertension, edema, hypokalemia, excessive increase in weight, and increase in heart size are signs of overdosage of fludrocortisone acetate. When these are noted, administration of the drug should be discontinued, after which the symptoms will usually subside within several days; subsequent treatment with fludrocortisone acetate should be with a reduced dose. Muscular weakness may develop due to excessive potassium loss and can be treated by administering a potassium supplement. Regular monitoring of blood pressure and serum electrolytes can help to prevent overdosage (see WARNINGS). DOSAGE AND ADMINISTRATION Dosage depends on the severity of the disease and the response of the patient. Patients should be continually monitored for signs that indicate dosage adjustment is necessary, such as remissions or exacerbations of the disease and stress (surgery, infection, trauma)(see WARNINGS and PRECAUTIONS, General). Addison's Disease In Addison's disease, the combination of Fludrocortisone Acetate tablets with a glucocorticoid such as hydrocortisone or cortisone provides substitution therapy approximating normal adrenal activity with minimal risks of unwanted effects. The usual dose is 0.1 mg of Fludrocortisone Acetate daily, although dosage ranging from 0.1 mg three times a week to 0.2 mg. daily has been employed. In the event transient hypertension develops as a consequence of therapy, the dose should be reduced to 0.05 mg. daily. Fludrocortisone Acetate is preferably administered in conjunction with cortisone (10 mg. to 37.5 mg. daily in divided doses) or hydrocortisone (10 mg. to 30 mg. daily in divided doses). Salt-Losing Adrenogenital Syndrome The recommended dosage for treating the salt-losing adrenogenital syndrome is 0.1 mg. to 0.2 mg. of Fludrocortisone Acetate daily. Storage Store at room temperature; avoid excessive heat. (E.R. Squibb & Sons, 11/91, J3-566C) (91/11) HOW SUPPLIED - EQUIVALENTS NOT AVAILABLE Tablet, Uncoated - Oral - 0.1 mg 100's $44.86 FLORINEF ACETATE, Bristol-Myers Squibb 00003-0429-50*