The P-I-E-N-O Parkinsn's List Drug Database

fludrocortisone acetate / Florineff^TM

ORTH. HYPOTENSION: HIGH RISK

Description: Fludrocortisone is a potent, synthetic mineralocorticoid. It is not a glucocorticoid like prednisone or dexamethasone. Fludrocortisone has extremely high sodium-retaining activity compared with glucocorticoids such as hydrocortisone, which possess some mineralocorticoid activity. Fludrocortisone is used as replacement therapy in patients with adrenocortical insufficiency and salt-losing adrenogenital syndrome. Fludrocortisone was approved by the FDA in 1954.

Mechanism of Action: Endogenous corticosteroids are secreted by the adrenal cortex; their effects are believed to be due to modification of enzymatic activity rather than to a direct hormone-induced action. Fludrocortisone mimics the actions of aldosterone, an endogenous mineralocorticoid. Mineralocorticoids alter electrolyte and fluid balance by facilitating sodium resorption and hydrogen and potassium excretion at the level of the distal renal tubule, resulting in edema and hypertension.

Pharmacokinetics: Fludrocortisone is absorbed rapidly from the GI tract and reaches peak plasma concentration within 1.5 hours. The circulating drug binds extensively to the plasma proteins albumin and transcortin, and only the unbound portion of a dose is active. Systemic fludrocortisone is quickly distributed into the kidneys, intestines, skin, liver, and muscle. Corticosteroids distribute into breast milk and cross the placenta. Fludrocortisone is metabolized by the liver to inactive metabolites. These inactive metabolites, as well as a small portion of unchanged drug, are excreted in the urine. The biological half-life of fludrocortisone is 18-36 hours.

CONTRAINDICATIONS/PRECAUTIONS:

Because of the high sodium-retaining activity of fludrocortisone, the drug should be used with extreme caution in patients with congestive heart failure, hypertension, renal disease, or cardiac disease. Therapy should be discontinued if significant weight gain, cardiac enlargement, blood pressure increase, or edema occurs.

Adequate glucocorticoid therapy should be used concomitantly with fludrocortisone therapy in treating adrenal insufficiency or salt-losing adrenogenital syndrome.

Patients with Addison's disease who receive fludrocortisone can exhibit an exaggerated response to the drug, and therapy should be discontinued if significant weight gain, cardiac enlargement, blood pressure increase, or edema occurs.

If fludrocortisone-induced edema develops, dietary sodium should be restricted because a high sodium intake can enhance sodium retention and potassium loss. Potassium supplements should be administered as necessary.

Pregnancy studies involving fludrocortisone use have not been done in humans. Use of fludrocortisone during pregnancy ahould be avoided unless the potential therapeutic benefit justifies the potential risk to the fetus. Infants born to mothers who have taken substantial doses of corticosteroids during pregnancy should be monitored for signs of hypoadrenanlism.

DRUG INTERACTIONS: Hepatic microsomal enzyme inducers, including barbiturates, phenytoin, and rifampin, can increase the hepatic metabolism of corticosteroids. Dosages of fludrocortisone may require adjustment if these agents are initiated or withdrawn during therapy.

Fludrocortisone can have profound effects on sodium-potassium balance. Other drugs that cause hypokalemia should be used cautiously with fludrocortisone. These include: amphotericin B, thiazide diuretics, and loop diuretics. Because hypokalemia can predispose a patient receiving digoxin to digitalis toxicity, fludrocortisone should be used cautiously in any patients receiving cardiac glycosides. Sodium retention can lead to fluid retention and edema, so fludrocortisone should be used cautiously in patients receiving androgens because these agents also can cause edema. NSAIDs also can affect sodium and fluid balance. Fludrocortisone and NSAIDs should be used together cautiously.

ADVERSE REACTIONS: Fludrocortisone has potent mineralocorticoid properties and can cause fluid imbalance, electrolyte imbalance (particularly hypokalemia), edema, congestive heart failure, and hypertension.

A hypokalemic syndrome also can be associated with fludrocortisone therapy and includes nausea/vomiting, orthostatic hypotension, QT prolongation, ST-T wave changes, severe weakness of the extremities, anorexia, and muscle cramping and pain.

Adverse CNS effects reported during fludrocortisone therapy include dizziness and headache.

PATIENT INFORMATION:

What do fludrocortisone tablets do?

Fludrocortisone (Florinef^TM ) is a corticosteroid. Flludrocortisone causes the body to retain salt and water. Fludrocortisone replaces the natural steroids that are lacking in patients with underactive adrenal glands. Fludrocortisone also treats a salt-losing condition called adrenogenital syndrome. Generic fludrocortisone tablets are not yet available.

What should my doctor, dentist, or pharmacist know before I take fludrocortisone?

They need to know if you have any of these conditions:

• heart disease
• high blood pressure
• kidney disease
• over-or underactive thyroid
• an unusual or allergic reaction to fludrocortisone, other corticosteroids, medicines, foods, dyes, or preservatives
• pregnant or trying to get pregnant
• breast-feeding

How should I take this medicine?

Take fludrocortisone tablets by mouth. Follow the directions on the prescription label. Swallow the tablets with a drink of water. Take with food or milk to avoid stomach upset. If you are only taking fludrocortisone once a day, take it in the morning, unless otherwise directed, which is the time your body normally secretes cortisol. Take your doses at regular intervals. Do not take your medicine more often than directed.

Special precautions for use in children:

Long-term use in children can inhibit growth.

What if I miss a dose?

If you miss a dose, take it a soon as you can. If it is almost time for your next dose, consult your doctor or pharmacist. You may need to miss a dose or take a double dose, depending on your condition and treatment. Do not take double or extra doses without advice.

What other medicines can interact with fludrocortisone?

• amphotericin B
• antiinflammatory drugs (NSAIDs, such as ibuprofen)
• barbiturate medicines for inducing sleep or treating seizures (convulsions)
• heart medicines such as digoxin
• male hormones
• phenytoin
• rifampin
• water pills

Tell your doctor or pharmacist: about all other medicines you are taking, including non-prescription medicines; if you are a frequent user of drinks with caffeine or alcohol; if you smoke; or if you use illegal drugs. These may affect the way your medicine works. Check before stopping or starting any of your medicines.

What side effects may I notice from taking fludrocortisone?

Serious side effects with fludrocortisone include:

• difficulty breathing or shortness of breath
• headache, severe or continuing
• irregular heartbeat
• loss of appetite
• mental depression, mood swings
• muscle weakness, cramps or pain
• nausea, vomiting
• skin rash or itching
• sudden weight gain
• swelling of face, nasal passages, or eyelids
• swelling of the feet or legs
• unusual tiredness

Call your doctor as soon as you can if you get any of these side effects.

Minor side effects with fludrocortisone include:

• dizziness
• increased appetite
• restlessness
• trouble sleeping
• upset stomach

Let your doctor know about these side effects if they do not go away or if they annoy you.

What do I need to watch for while I take fludrocortisone?

Visit your doctor for regular checks on your progress. If you are taking fludrocortisone over a prolonged period, carry an identification card with your name and address, the type and dose of your medicine, and your doctor's name and address. Do not suddenly stop taking fludrocortisone. Follow the advice of your doctor.

Avoid contact with people who have an infection. You will have an increased risk from infection while taking fludrocortisone. Do not receive any vaccinations as you may get a strong reaction, and avoid people who have recently taken oral polio vaccine. Tell your doctor if you are exposed to anyone with measles or chickenpox, or if you develop sores or blisters that do not heal properly.

If you are going to have surgery, tell your doctor or dentist that you have taken fludrocortisone within the last twelve months.

You may need to watch your diet. Your body can lose potassium while you are taking fludrocortisone. Ask your doctor about your diet.

Alcohol can increase the risk of getting serious side effects while you are taking fludrocortisone. Avoid alcoholic drinks.

Fludrocortisone can interfere with certain lab tests and can cause false skin test results.

Where can I keep my medicine?

Keep out of the reach of children in a container that small children cannot open.

Store at room temperature between 15 and 30C (59 and 86F). Protect from excessive heat. Throw away any unused medicine after the expiration date.

Parkinsn's Archive Treasures Page

John Cottingham is the webmaster of this site.