Information for the public

Summary of possible benefits and harms

How well does fludrocortisone work?

There has been limited research into the use of fludrocortisone for treating postural hypotension.

One very small study compared fludrocortisone with a 'dummy' tablet (known as placebo) in 6 people with postural hypotension caused by diabetes. This found that fludrocortisone taken for 3 weeks improved postural hypotension more than the 'dummy' tablet.

Another small study compared fludrocortisone with non-drug treatments in 17 people with postural hypotension and Parkinson's disease. This found that 3 weeks treatment with fludrocortisone slightly improved symptoms of postural hypotension.

Another slightly larger study compared fludrocortisone with a 'dummy' tablet in 100 people with chronic fatigue syndrome (feeling very tired and generally unwell). This study found that fludrocortisone taken for 9 weeks did not improve wellness compared with the 'dummy' tablet.

These studies provide very limited evidence that fludrocortisone may improve postural hypotension. However, because none of the studies lasted for more than 9 weeks and they did not include many people, the results are not conclusive.

What are the possible harms or side effects?

The manufacturers of fludrocortisone recommend that it is not suitable for people with certain serious bacterial or viral infections unless they receive particular treatment for the infection. They also recommend that blood pressure, swelling, weight gain, salt levels and side effects associated with corticosteroids (similar drugs to fludrocortisone) should be monitored in people receiving fludrocortisone. Oral steroids including fludrocortisone may weaken the immune system, which could increase the risk of getting a serious infection. There is a warning that people taking fludrocortisone who haven't had chicken pox should keep away from anyone with chicken pox. Exposure to measles and shingles should also be avoided. People should seek medical advice if they are exposed to chicken pox, shingles or measles while taking fludrocortisone.

Oral steroids including fludrocortisone can cause serious mental health problems. They can affect about 5 in every 100 people taking medicines like fludrocortisone.

If oral steroids like fludrocortisone have been taken for more than 3 weeks, the dose should be gradually reduced when it is stopped unless a healthcare professional advises otherwise. People taking fludrocortisone should carry a steroid treatment card. This card should always be carried with them and shown to anyone who treats them (for example, a doctor, nurse, pharmacist or dentist).

About a quarter of those (13 out of 50) taking fludrocortisone in the 9‑week study stopped taking the drug. Reasons included: depression (4 people), abdominal (stomach) discomfort (2 people), worsening symptoms (2 people), high blood pressure (1 person), and worsening headaches (1 person). Out of 50 people taking the 'dummy' tablet, 8 stopped taking it. At least 1 side effect was reported by around 30 in every 50 people taking fludrocortisone compared with around 35 in every 50 people taking the 'dummy' tablet.

In the study in 6 people with postural hypotension caused by diabetes, 2 people developed ankle swelling while taking fludrocortisone. This quickly got better when fludrocortisone was stopped.

The 3 studies of the use of fludrocortisone for postural hypotension lasted for no longer than 9 weeks, so they don't tell us how well fludrocortisone works or how safe it is if taken for longer than this. Another study did look at the possible harms or side effects of fludrocortisone in older people taking it for about 1 year. This study only looked at the possible harms or side effects of the drug and not at how well the drug works. It had several limitations including that it did not have a comparison group, but found that 38 of 64 people (59%) had side effects with 17 people stopping taking the drug due to these side effects. Reasons for stopping taking the drug were: heart failure (7 people), high blood pressure (4 people), depression (3 people), thought by the patient to be of no benefit (2 people) and stroke (1 person).

Please note that the results of the research studies only indicate the benefits and harms for the population in the studies. It is not possible to predict what the benefits and harms will be for an individual patient being treated with fludrocortisone.