Why Does Adrenal Insufficiency Need a Plan Before Surgery or During Infection?

The pre-operative questionnaire has a box marked chronic conditions, and Maria writes two words in it: Addison’s disease. The nurse reads them, looks up, and puts her pen down. Everything else on the form, the knee that needs repairing, the list of allergies, can wait a minute. This is the part that needs a conversation.

Moments like that are exactly why adrenal insufficiency surgery precautions exist. Maria feels well. She has taken her replacement tablets every morning for eleven years and thinks of her condition as background noise. But an operation, or a bout of flu that keeps her in bed, is not background noise to her body. It is a demand her adrenal glands cannot meet on their own.

This explainer walks through what actually happens to cortisol under stress, what a surgical and sick-day plan usually contains, and the warning signs that mean it is time to stop reading and call for help.

What is adrenal insufficiency, in plain language?

Two small glands sit on top of the kidneys like caps. These are the adrenal glands, and among the hormones they make, cortisol matters most for this conversation. Cortisol is a steroid hormone that keeps blood pressure steady, keeps glucose available to the brain and muscles, helps the body hold on to salt and water, and dampens inflammation when it threatens to run out of control. Adrenal insufficiency simply means the glands cannot make enough of it.

Doctors divide the condition into two broad types. Primary adrenal insufficiency, often called Addison’s disease, is a problem in the gland itself; in many countries the usual cause is the immune system mistakenly attacking adrenal tissue, according to the NHS. Because the gland is damaged, aldosterone (the hormone that manages salt and fluid balance) is usually lost as well. Secondary adrenal insufficiency comes from upstream: the pituitary gland at the base of the brain stops sending the chemical signal that tells the adrenals to work. The most common reason for that, as NIH describes, is long-term treatment with glucocorticoid medicines for another condition such as asthma, rheumatoid arthritis or inflammatory bowel disease. The adrenals are healthy but have been told to rest for so long that they cannot answer quickly.

Either way, treatment means replacement: a daily glucocorticoid, most commonly the generic medicine hydrocortisone, sometimes prednisolone or another agent, and in primary disease usually a mineralocorticoid such as fludrocortisone to stand in for aldosterone. Taken consistently, replacement lets most people live and work normally. The catch is in the word consistently. A tablet delivers a fixed amount. A healthy gland delivers what the moment requires.

What actually happens to cortisol during surgery or infection?

Picture the body’s stress response as a thermostat rather than a switch. The hypothalamus and pituitary in the brain sense threat, whether a surgeon’s incision, a spiking fever or a night of vomiting, and they turn the adrenal glands up. In a healthy person, cortisol output climbs steeply within minutes and stays elevated for as long as the stress lasts. That extra cortisol does quiet but essential work. It keeps blood vessels responsive to adrenaline so blood pressure does not collapse. It nudges the liver to release glucose so the brain is fuelled. It restrains the inflammatory cascade that surgery and infection unleash, preventing that cascade from tipping into shock.

Someone with adrenal insufficiency has no thermostat. Their morning tablet has been absorbed and is being cleared from the body on its usual schedule regardless of what the day brings. When the surgeon begins or the infection takes hold, demand rises and supply does not. The Mayo Clinic describes the result: blood pressure falls, sodium drops, potassium can climb in primary disease, glucose may dip, and the person becomes weak, confused and dehydrated.

Infection adds a second, sneakier problem. Vomiting or severe diarrhoea means the replacement tablet may never be absorbed at all. A person can take their medicine faithfully and still, in effect, be unmedicated. Fever raises the body’s metabolic demand at the same moment absorption becomes unreliable. That combination explains why a stomach bug, ordinarily a miserable few days for anyone else, can be dangerous for someone whose adrenal glands have no reserve. It also explains why the plan for infection and the plan for surgery share the same logic: anticipate the demand, and supply the hormone by a route that will reliably work.

Adrenal insufficiency surgery precautions: what a plan usually covers

A good plan is less a document than a chain of people who all know the same thing. The NHS advises that anyone with Addison’s disease tells their surgeon, anaesthetist and dentist before any procedure, and that they carry evidence of the diagnosis at all times. Everything else follows from that first disclosure.

In practice, the plan tends to cover five areas. First, communication: the endocrinology team, the surgical team and the anaesthetist agree in advance how replacement will be handled, often in a written letter that travels with the patient. Second, the route of the medicine. A person who is fasting before a general anaesthetic cannot rely on tablets, so glucocorticoid is typically given by injection or intravenous drip around the time of anaesthesia and for as long afterwards as the team judges necessary. Third, monitoring: blood pressure, blood glucose and electrolytes such as sodium and potassium are watched more closely than they would be for another patient having the same operation. Fourth, a step-down: how and when the temporarily raised replacement returns to the usual daily amount, which depends on the size of the operation and how recovery goes. Fifth, the fallback: who to call, and what to do, if vomiting, fever or dizziness appear once the person is home.

None of these steps involve the patient deciding amounts. The numbers belong to the prescribing clinician and are written into the plan. What the patient owns is the disclosure, the emergency card, the injectable kit and the confidence to speak up if something in the chain seems to have been missed. A plan that lives in a filing cabinet protects nobody; a plan the anaesthetist reads on the morning of surgery protects a great deal.

Adrenal crisis symptoms: why this is a medical emergency

Adrenal crisis is the name for what happens when cortisol demand outstrips supply so badly that the circulation begins to fail. MedlinePlus lists the picture clinicians look for: sudden, severe pain in the lower back, abdomen or legs; vomiting and diarrhoea leading to dehydration; low blood pressure; confusion or loss of consciousness; profound weakness; and sometimes fever. The Cleveland Clinic and the Mayo Clinic describe the same cluster and add that, untreated, crisis can progress to shock and death. Treated promptly with intravenous fluids and injected glucocorticoid, most people recover.

Why does it escalate so fast? Because the systems cortisol supports are the ones that keep a person upright. Low cortisol lets blood vessels relax when they should be tightening, so pressure falls. In primary disease the missing aldosterone means the kidneys leak sodium and water while holding potassium, so dehydration deepens and the heart’s rhythm can be affected. Falling glucose starves the brain, which is why confusion appears. Each problem worsens the others.

The triggers are predictable, which is the whole point of having a plan. Infection, especially with vomiting, is the most common. Surgery, injury, a broken bone, a severe emotional shock or, in someone on long-term steroids for another condition, stopping that medicine abruptly can all tip the balance. A person can also drift into crisis through missed doses over several days, though this is less common than an acute trigger.

The response is not something a patient works out at home. Emergency injection from the kit, if one has been prescribed, followed immediately by emergency services, is the sequence set out in most written plans. The details of when and how belong to the team that wrote the plan.

Who needs a surgical plan, and who is usually asked to wait?

Everyone with a confirmed diagnosis of adrenal insufficiency needs one, and the list is longer than many people assume. It includes people with Addison’s disease, people whose pituitary has been damaged by a tumour, surgery or radiotherapy, people born with congenital adrenal hyperplasia, and the large group who have taken glucocorticoid medicines for months or years for asthma, arthritis, lupus, inflammatory bowel disease or after an organ transplant. NIH notes that this last group may have suppressed adrenal function without ever having been told the words adrenal insufficiency. Anyone in that category should raise it at pre-operative assessment even if nobody asks.

Who is asked to wait? Elective, non-urgent surgery is commonly postponed when a person is acutely unwell with an infection, because operating during an illness stacks one stress on another. Someone who has recently stopped long-term steroids and whose adrenal recovery has not been checked may be asked to have blood tests first, so the team knows whether cover is needed. A person whose diagnosis is suspected but not confirmed is often tested before, rather than after, an operation. In each case the aim is to remove uncertainty, not to deny care.

Emergency surgery is different. Nobody waits for an appendix to rupture while the endocrine team is paged. Instead, the anaesthetist assumes the adrenal glands cannot respond and gives glucocorticoid cover as standard. This is where the steroid emergency card earns its place: an unconscious patient cannot explain their history, and the card does it for them.

Pregnancy, childbirth and dental procedures each have their own considerations that the treating team will discuss. The common thread is that the decision about cover, its route and its duration always rests with the clinicians who know the patient’s history.

Sick day rules for adrenal insufficiency: what they actually mean

Sick day rules are the written instructions an endocrinology team gives a person so they know what to do with their replacement when they fall ill. The phrase is borrowed from diabetes care and it means the same thing: a pre-agreed response to a predictable problem, so nobody is improvising while feverish at three in the morning.

The NHS describes the principle. When someone with Addison’s disease develops a fever, an infection needing antibiotics or an illness that keeps them in bed, their glucocorticoid is temporarily increased, with the exact amount and duration set out by their own team. The increase mimics, crudely but effectively, what a healthy adrenal gland would do. Once the illness passes, the replacement returns to the usual daily amount according to the written instruction. Fludrocortisone, where taken, is generally not adjusted by the patient.

The rules also cover the scenario tablets cannot solve. If a person is vomiting and cannot keep medicine down, or has severe diarrhoea, the tablet route is unreliable and an injection is needed. Most plans instruct the person or a family member to use the prescribed injectable kit and then seek emergency care, rather than wait to see whether the next tablet stays down.

What sick day rules are not is a licence to self-medicate. They are a prescription with conditions attached, and the conditions matter. A person who is unsure whether their illness meets the threshold in their rules should call their team or an out-of-hours service rather than guess in either direction. Written rules that are stuck to the fridge, understood by the household and reviewed at each clinic visit are worth more than a vague memory of what a doctor once said.

Stress dose steroids before surgery: what happens on the day

The phrase stress dose steroids describes the temporary extra glucocorticoid given around an operation to stand in for the cortisol surge the body cannot produce. Here is how a typical day unfolds, with the caveat that every team adapts it.

Before arrival, the person has usually been told whether to take their normal morning replacement despite fasting; many teams allow tablets with a sip of water, but this is an individual instruction. At the hospital, the anaesthetist confirms the diagnosis, checks the emergency card or letter, and notes the plan on the chart. A wristband or alert flag may be added so every member of staff who touches the record sees it.

At the start of anaesthesia, glucocorticoid is given by injection into a vein. For a short, minor procedure this single injection may be all that is needed. For longer or more invasive surgery, the medicine is continued afterwards, either as repeated injections or as a continuous infusion, until the person is reliably eating, drinking and keeping tablets down. Throughout, nurses monitor blood pressure and blood glucose more frequently than for a comparable patient without the condition, and blood tests check sodium and potassium.

For procedures under local anaesthetic, such as a straightforward dental filling or a skin biopsy, many teams judge that the stress is small enough that the usual replacement suffices, sometimes with a modest adjustment. This is not a decision to make in the dentist’s chair; it should be agreed beforehand.

The person’s role on the day is simpler than the medical choreography suggests: confirm the diagnosis to every clinician who introduces themselves, keep the emergency card visible, and say something if the plan discussed in clinic does not seem to be happening.

How do precautions differ between a dental filling, day surgery and a major operation?

Not every stress is equal, and plans scale accordingly. The table below summarises the general pattern described by the NHS, Mayo Clinic and NIH. It is a map, not a prescription; the specific response for any individual is set by their own team.

Situation	Stress on the body	What the plan usually involves
Routine dental check or filling under local anaesthetic	Low	Usual replacement, agreed in advance with the dentist; some teams advise a small temporary adjustment
Minor day-case procedure (for example a skin lesion removal or endoscopy)	Low to moderate	Usual replacement, often with a single injected glucocorticoid around the procedure
Major surgery under general anaesthetic	High	Injected glucocorticoid at induction, continued by injection or infusion until eating and drinking normally, then a stepped return to usual replacement
Fever or infection needing bed rest, tablets tolerated	Moderate	Sick day rules: temporary increase in glucocorticoid as written by the team, extra fluids
Vomiting or severe diarrhoea, tablets not tolerated	High and unpredictable	Emergency injection from the kit, then emergency care for fluids and further treatment
Serious injury or emergency surgery	High	Clinicians give glucocorticoid cover as standard; the emergency card speaks for the patient

Two patterns stand out. The route of the medicine matters as much as the amount: whenever swallowing cannot be relied upon, the plan switches to injection. And the trigger for escalation is the body’s condition, not the calendar. A person recovering well from a large operation may step down sooner than expected; a person with a stubborn wound infection may need cover for longer. The team reads the patient, not the table.

Why infection with vomiting is the most dangerous everyday scenario

Ask endocrinologists what keeps them awake and the answer is rarely the operating theatre, where an anaesthetist is standing at the patient’s head. It is the ordinary gastroenteritis that arrives on a Sunday evening.

Three things go wrong at once. The infection itself raises cortisol demand, as any illness does. Vomiting empties the stomach before the replacement tablet has dissolved and crossed into the bloodstream, so the morning medicine may simply not count. And fluid loss from vomiting and diarrhoea, in a person with primary disease who also lacks aldosterone, accelerates the loss of sodium and water that the kidneys are already struggling to hold. The Mayo Clinic notes that dehydration and low blood pressure are central features of crisis, and a stomach bug delivers both.

The trap is reassurance. Someone who vomits once, feels a little better and decides to try another tablet in an hour is making a reasonable-sounding decision that written sick day rules generally advise against. The NHS guidance is that a person who cannot keep medicine down needs an injection and medical attention. Waiting to see whether the next tablet stays down costs time that a falling blood pressure does not give back.

This is why the injectable kit is prescribed for home and why family members are taught to use it. It is also why many teams encourage people to keep their kit where they will actually be when unwell, at the bedside rather than in a distant cupboard, and to check it has not expired at each clinic review.

A less dramatic version of the same lesson applies to fever without vomiting. Sick day rules exist to be used. Sitting out a flu on the usual replacement because the symptoms do not feel severe is a common way that a manageable illness becomes an admission.

What the days and weeks after surgery usually look like

Recovery has two timelines running side by side: the ordinary one for the operation, and the endocrine one for stepping cover back down.

In the first hours after a large operation, glucocorticoid continues by injection or drip. Once the person is awake, drinking and keeping food down, the team begins to reduce it. For minor procedures this can mean returning to usual tablets the same day; for major surgery the step-down commonly unfolds over several days and is paced by how the person is doing rather than by a fixed schedule. The NHS emphasises that anyone who has had surgery should follow the instructions given by their own care team about when and how to return to their usual replacement.

During this phase, the things worth watching are the same things that trigger sick day rules in the first place. Nausea from anaesthesia or painkillers can interfere with tablets just as a stomach bug would. A wound infection or chest infection raises demand again. Poor appetite, poor sleep and pain all add to the body’s load. Nursing staff will be monitoring blood pressure and glucose, but once home the person and their household become the monitors.

By the second and third weeks, most people who are healing well are back on their usual replacement and their usual routine. Fatigue that seems out of proportion to the operation, persistent dizziness on standing, or a return of nausea are worth reporting rather than attributing to a slow recovery. A follow-up with the endocrine team, even a phone call, is a reasonable request after any major procedure.

The key habit for the weeks after surgery is the same as before it: keep the emergency card and injectable kit within reach, and treat any new illness as a sick day rather than a nuisance.

The steroid emergency card, medical alert jewelry and telling every clinician

A plan that only the patient knows about is a plan that fails the moment the patient cannot speak. Three tools solve that problem.

The first is the steroid emergency card. In the UK the NHS provides a standard card stating that the holder depends on steroid replacement and must not have it interrupted; similar cards and letters exist in other health systems. It is designed to be read by an emergency clinician who has never met the person. Kept in a wallet or phone case, it changes what happens in the first ten minutes of an emergency department visit.

The second is medical alert jewelry: a bracelet or pendant engraved with the diagnosis. It is the backup for the card, useful when a bag has been left behind or a person has collapsed away from home. Some people prefer a wallet card alone; the point is that at least one form of identification is always on the body.

The third is habit. Telling every new clinician, every dentist, every physiotherapist and every pharmacist about the diagnosis feels repetitive and is worth doing anyway. The NHS explicitly advises telling the dentist before any dental work. Hospital records are not always shared across departments, and a locum on a night shift may not scroll far enough back.

Family and close friends form the last line. Anyone who might find the person unwell should know where the injectable kit lives, how it is used and that the next step after using it is calling emergency services, not waiting for improvement. Many endocrine clinics offer teaching sessions for relatives; asking for one is a fair request, not an imposition.

What people often get wrong

Myths about adrenal insufficiency tend to be comfortable ones, which is what makes them dangerous.

The first is that years of stability mean the plan is no longer needed. Stability on replacement says nothing about reserve. The gland that could not respond eleven years ago still cannot respond, and surgery or infection tests exactly that.

The second is that replacement steroids are the same as the high-dose steroids used to treat inflammation, with the same long-term risks. Replacement aims to restore what a healthy body makes, no more. The Cleveland Clinic and Mayo Clinic both describe it as physiological replacement, and the temporary increases for illness or surgery are short-lived by design.

The third is that only people with a formal Addison’s diagnosis are affected. NIH is clear that long-term glucocorticoid treatment for other conditions can suppress the adrenal axis, and people in this group are frequently the ones who arrive at surgery with no plan at all because nobody used the words.

The fourth is that feeling well after an operation means cover can stop early. The step-down is paced by the team for a reason; a wound infection on day four can raise demand again.

The fifth is that vomiting once is not a big deal. Written sick day rules generally treat inability to keep tablets down as the signal for injection and medical attention, not for patience.

The last is the opposite error: that every minor stress needs extra medicine. A routine dental cleaning under local anaesthetic is not major surgery, and taking unnecessary extra glucocorticoid has its own downsides. The answer to every one of these is the same. Ask the team, get it in writing, and follow what is written.

Questions to ask your care team

The most useful conversations happen before a procedure is booked and again at every routine review. These questions tend to surface the gaps.

• Which type of adrenal insufficiency do I have, and does that change what needs to happen around surgery or illness?
• Can I have a written surgical plan that I can hand to the anaesthetist and surgeon, and who updates it if my treatment changes?
• Should I take my usual morning replacement on the day of surgery if I am fasting?
• For this particular procedure, will I need injected cover, and for how long afterwards is it likely to continue?
• What are my written sick day rules, and what specifically counts as an illness serious enough to use them?
• Do I have an injectable emergency kit at home, is it in date, and who in my household has been shown how to use it?
• Where do I get a steroid emergency card, and should I also wear medical alert jewelry?
• Which symptoms after surgery or during an infection mean I should call the clinic, and which mean I should call emergency services straight away?
• Does my dentist need to do anything differently, and will you write to them?
• If I am travelling, what should I carry, and is a letter explaining my kit useful at security or abroad?
• If I was diagnosed after long-term steroid treatment for another condition, is there a chance my adrenal function will recover, and how will that be checked?

Writing the answers down, or asking for them in a letter, turns a good conversation into a plan that survives a change of doctor, a new hospital or a bad night. Bring the list to the pre-operative assessment rather than trying to remember it while the nurse is taking blood pressure.

When to call your doctor

Two levels of response apply, and the plan a person carries should make the line between them clear.

Call the endocrine team, primary care doctor or an out-of-hours service the same day when there is a fever, a new infection, an illness that keeps you in bed, persistent nausea after an operation, or any uncertainty about whether sick day rules apply. Call as well if the injectable kit has been used and you want confirmation of what to do next, if a new medicine has been prescribed by a clinician who may not know your history, or if an unplanned procedure is being arranged.

Call emergency services, or have someone drive you to an emergency department, without waiting when any of the following appear, particularly during illness or in the days after surgery. MedlinePlus, the Mayo Clinic and the Cleveland Clinic list these as features of adrenal crisis:

• Vomiting or diarrhoea so that replacement tablets cannot be kept down
• Severe dizziness, fainting or blood pressure known to be low
• Sudden severe pain in the lower back, abdomen or legs
• Confusion, unusual drowsiness or difficulty staying awake
• Profound weakness that is out of proportion to the illness
• Rapid heartbeat with cold, clammy skin
• Any situation where the emergency injection has been used

Tell the call handler and the first clinician you see that you have adrenal insufficiency and need urgent steroid cover, and show the emergency card. If a relative is with you, they should say it for you. None of these steps replace the individual plan your team has written; they are the reason the plan exists. When in doubt, the safer error is to call.

Frequently asked questions

What are the early adrenal crisis symptoms I should recognise?

Early features are usually nausea, vomiting, dizziness on standing, unusual weakness and abdominal or back pain, progressing to confusion and very low blood pressure. MedlinePlus and the Mayo Clinic describe this cluster, often triggered by infection, injury or surgery. Because the picture escalates quickly, written plans treat vomiting that prevents tablets from staying down as the point to use the emergency injection and call for help.

What are sick day rules for adrenal insufficiency?

Sick day rules are written instructions from your endocrine team explaining how to adjust glucocorticoid replacement when you have a fever, an infection or an illness that keeps you in bed, and what to do if you cannot keep tablets down. The NHS describes a temporary increase during illness, with the exact amounts set by your own clinician. The rules are personal and should be reviewed at each appointment.

What does stress dose steroids before surgery actually mean?

It means the temporary extra glucocorticoid given around an operation to replace the cortisol surge a healthy body would produce. For a general anaesthetic it is usually injected into a vein at the start and continued by injection or infusion until you are eating and drinking normally. The anaesthetist and your endocrine team decide the route, the amount and how long it continues based on the size of the procedure.

Do I need a steroid emergency card if I already wear a medical bracelet?

Carrying both is generally advised. The card explains in words that your steroid replacement must not be interrupted and that you need urgent cover if unwell, which an emergency clinician can read at a glance. The bracelet is the backup when a wallet or bag is missing. The NHS recommends that people with Addison’s disease carry identification at all times and inform every clinician, including dentists.

Does a dental filling under local anaesthetic need extra steroid cover?

Often it does not, because the stress on the body is small, but this should be agreed with your endocrine team and your dentist in advance rather than assumed. Some teams advise a small temporary adjustment for longer or more involved dental work. The NHS specifically advises telling your dentist about Addison’s disease before any treatment so the plan is settled beforehand.

Why is vomiting so dangerous for someone with adrenal insufficiency?

A tablet that is vomited up may never enter the bloodstream, so you can take your replacement faithfully and still be effectively unmedicated at the moment your body needs more cortisol, not less. Vomiting also causes fluid and salt loss, which in primary disease is worsened by missing aldosterone. Written plans therefore treat inability to keep tablets down as the trigger for an emergency injection and medical attention.

Can adrenal function recover after long-term steroid treatment for another condition?

It can in many people, because the adrenal glands themselves are healthy and were only suppressed by the medicine, but recovery is gradual and varies widely, according to NIH. The safe assumption until tests show otherwise is that reserve is absent, so surgical cover and sick day rules still apply. Your team can arrange blood tests to check whether the axis has recovered before removing those precautions.

Who gives the steroid cover if I need emergency surgery and cannot speak?

The anaesthetist and emergency team do, and they will assume your adrenal glands cannot respond as soon as they know the diagnosis. That knowledge comes from your steroid emergency card, medical alert jewelry, a relative who can speak for you, or your hospital record. This is why carrying identification on your body, not only in a bag, is stressed by the NHS and other guidance.

How long after major surgery does the extra steroid usually continue?

It continues until you are reliably eating, drinking and keeping tablets down, then steps down over a period the team sets, commonly several days for larger operations and the same day for minor ones. The pace depends on how recovery is going; a wound or chest infection can extend it. Follow the written instructions from your own care team rather than a general timeline.

Should family members be taught to use my emergency injection kit?

Yes, in almost every plan. If you are vomiting, confused or drowsy you may be unable to inject yourself, and someone in the household knowing where the kit is and how to use it can be decisive. Most endocrine clinics offer teaching for relatives on request. The agreed next step after any use of the kit is to call emergency services, not to wait and see.

References

• NHS: Addison's disease, treatment
• MedlinePlus: Acute adrenal crisis
• NIH NIDDK: Adrenal insufficiency and Addison's disease

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.