Hyperinsulinaemic hypoglycaemia is a serious condition where the pancreas releases too much insulin, causing dangerously low blood sugar levels. Treatment focuses on protecting the brain from damage, controlling blood sugar, and managing insulin production through medications or, when necessary, surgical intervention.

Understanding Treatment Goals in Hyperinsulinaemic Hypoglycaemia

When someone is diagnosed with hyperinsulinaemic hypoglycaemia, the main aim of treatment is to prevent brain damage by keeping blood sugar levels stable and within a safe range. The brain depends almost entirely on glucose for fuel, and when insulin levels are too high, glucose gets pulled out of the bloodstream too quickly. What makes this condition particularly dangerous is that excess insulin also blocks the body from producing ketone bodies, which are alternative fuels the brain can normally use when glucose is low. This double effect—low glucose and no backup fuel—puts the brain at serious risk, especially in babies and young children whose brains are still developing.^[1]

Treatment strategies depend heavily on several factors including the patient’s age, the severity of hypoglycaemia, whether the condition is temporary or permanent, and what is causing the excessive insulin secretion. In newborns, the condition may be linked to factors like maternal diabetes or birth complications, and it might resolve on its own within weeks or months. In other cases, the problem is due to genetic mutations affecting how the pancreatic beta cells work, requiring long-term medical management or even surgery.^[4]

Modern treatment involves a combination of approaches: medical therapies approved by healthcare guidelines, advanced imaging techniques to locate problem areas in the pancreas, and when medications fail, surgical options that have become more refined over recent years. There is also ongoing research into newer drugs being tested in clinical trials, offering hope for patients who do not respond well to current standard treatments.^[5]

Standard Medical Treatment

The first step in managing hyperinsulinaemic hypoglycaemia is to restore blood sugar levels immediately using intravenous dextrose (a form of glucose). When a baby or child arrives with dangerously low blood sugar, doctors give dextrose through a vein to quickly raise glucose levels and prevent brain damage. In severe cases, glucose infusion rates may need to be very high—sometimes 15 to 30 milligrams per kilogram per minute, which is much higher than normal. In fact, needing more than 8 milligrams per kilogram per minute strongly suggests hyperinsulinaemic hypoglycaemia as the cause.^[3]

Once blood sugar is stabilized, doctors prescribe medications to reduce insulin secretion or increase glucose availability. The first-line drug for controlling hypoglycaemia in this condition is diazoxide, which works by opening potassium channels in the pancreatic beta cells. When these channels are open, the cells release less insulin. Diazoxide is given by mouth, and the typical dose ranges from about 5 to 15 milligrams per kilogram per day, though some patients may need up to 20 milligrams per kilogram per day. Treatment with diazoxide can last for months or even years until the condition improves or resolves completely.^[9]

However, diazoxide does not work for everyone. It is ineffective in patients who have certain genetic mutations affecting the KATP channels (the potassium channels in beta cells), which are caused by mutations in the ABCC8 or KCNJ11 genes. These patients have what is called diazoxide-unresponsive hyperinsulinaemic hypoglycaemia. The drug also has side effects. Common ones include fluid retention, increased body hair growth, and stomach upset. More serious but rare side effects can include heart problems, though the direct link between diazoxide and severe complications like heart failure remains uncertain.^[13]

When diazoxide does not work or causes intolerable side effects, the next option is somatostatin analogues. These are synthetic versions of a natural hormone called somatostatin that inhibits insulin release. The two main drugs in this class are octreotide and lanreotide. Octreotide is usually given as an injection under the skin multiple times a day or through a continuous pump, at doses ranging from about 5 to 25 micrograms per kilogram per day. Lanreotide is a longer-acting form that can be given once a month, typically at doses of 30 to 120 milligrams per month.^[10]

Somatostatin analogues can be helpful in some patients, but they have limitations. One major problem is tachyphylaxis, which means the drug becomes less effective over time as the body’s receptors become less responsive. This happens because the receptors for somatostatin on the beta cells get downregulated with continuous exposure to the drug. Side effects are usually mild and include stomach problems like nausea, diarrhea, and abdominal discomfort. A more serious concern, especially in newborns, is the risk of necrotizing enterocolitis, a severe intestinal condition that can be life-threatening. Because of this risk, octreotide must be used with great caution in very young infants. Long-term use can also potentially slow growth, although this effect appears to be uncommon if the drug is stopped after a reasonable period.^[10]

Another medication sometimes used is nifedipine, a calcium channel blocker. Calcium channels play a role in triggering insulin release from beta cells, so blocking these channels can reduce insulin secretion. Nifedipine is typically given at doses of around 0.5 to 2 milligrams per kilogram per day. However, it is not as effective as diazoxide or somatostatin analogues and is usually considered when other options have failed or are not suitable. Side effects can include low blood pressure, flushing, and headaches.^[11]

In some cases, doctors may also use glucagon, a hormone that raises blood sugar by triggering the liver to release stored glucose. Glucagon can be given as an injection or through a continuous infusion pump. It is particularly useful in emergencies when blood sugar drops dangerously low and the patient cannot take food by mouth. However, glucagon is not a long-term solution because it can lose effectiveness over time and may cause side effects like nausea and vomiting.^[9]

Dietary management is also a crucial part of standard treatment. Infants and children with hyperinsulinaemic hypoglycaemia often need frequent feedings to maintain stable blood sugar levels. Some may require continuous feeding through a tube placed into the stomach, especially overnight, to prevent dangerous drops in glucose during sleep. High-carbohydrate snacks and meals help provide a steady supply of glucose. In severe cases, uncooked cornstarch may be added to the diet because it releases glucose slowly over several hours, helping to keep blood sugar levels more stable between meals.^[6]

Treatment Options Being Explored in Clinical Trials

For patients who do not respond to standard medications, researchers are testing several innovative treatments in clinical trials. One of the most promising drugs currently under investigation is sirolimus, also known as rapamycin. Sirolimus is an mTOR inhibitor, meaning it blocks a cellular pathway called mTOR (mechanistic target of rapamycin) that is involved in cell growth and metabolism. In hyperinsulinaemic hypoglycaemia, overactive mTOR signaling in beta cells can contribute to excessive insulin production. By blocking this pathway, sirolimus can reduce insulin secretion and help control blood sugar levels.^[8]

Early results from clinical trials of sirolimus have been encouraging. Some patients with severe, diazoxide-unresponsive hyperinsulinaemic hypoglycaemia who were previously difficult to manage showed improvement in their blood sugar control after starting sirolimus. The drug appears to be particularly helpful in patients with certain genetic forms of the condition and in those who would otherwise require surgery. Sirolimus is given by mouth, usually once or twice daily, and doses are adjusted based on blood levels of the drug to ensure safety and effectiveness.^[12]

However, sirolimus is not without risks. It suppresses the immune system, which can increase the risk of infections. Other side effects may include mouth ulcers, delayed wound healing, high cholesterol, and effects on blood cell counts. Because it is an immunosuppressant, patients taking sirolimus need careful monitoring with regular blood tests. Clinical trials are ongoing to better understand which patients benefit most from sirolimus, what the optimal dose is, and how long treatment should continue.^[8]

Another area of research involves developing newer, more selective somatostatin analogues. Current drugs like octreotide and lanreotide bind to several different types of somatostatin receptors throughout the body, which can cause unwanted side effects. Scientists are working on creating drugs that target only the specific receptors on pancreatic beta cells, which could make the treatment more effective and cause fewer problems. These drugs are still in early-phase clinical trials, and it will take time to know if they offer real advantages over existing treatments.^[10]

Researchers are also investigating the use of GLP-1 receptor antagonists. GLP-1 (glucagon-like peptide-1) is a hormone that stimulates insulin release after meals. In some forms of hyperinsulinaemic hypoglycaemia, particularly those that occur after eating or after weight-loss surgery, blocking GLP-1 might help reduce excessive insulin secretion. These drugs are in the experimental stage and are being tested in Phase I and Phase II trials to determine their safety and whether they effectively control blood sugar in patients with this condition.^[5]

Gene therapy is another exciting avenue being explored, although it is still in very early stages. Since many cases of congenital hyperinsulinaemic hypoglycaemia are caused by genetic mutations in key genes like ABCC8 and KCNJ11, researchers are investigating whether it might be possible to correct these mutations using gene-editing techniques. The idea would be to deliver a working copy of the gene to the pancreatic beta cells, allowing them to function normally. While this approach holds great promise, it faces significant technical challenges and is not yet being tested in human trials for this condition.^[4]

Clinical trials for hyperinsulinaemic hypoglycaemia are being conducted at specialized centers in several countries, including the United Kingdom, United States, and various locations in Europe. Patients with severe or medication-resistant forms of the condition may be eligible to participate in these studies. Participation in a clinical trial offers access to cutting-edge treatments that are not yet widely available, although it also involves some uncertainty about effectiveness and potential unknown side effects. Doctors can provide information about ongoing trials and help families decide whether enrollment might be appropriate.^[5]

Surgical Treatment Approaches

When medications cannot adequately control blood sugar levels, surgery may be necessary. The type of surgery depends on whether the hyperinsulinaemic hypoglycaemia is focal or diffuse. Focal hyperinsulinaemic hypoglycaemia means that only a small, localized area of the pancreas is producing excess insulin. This is essentially a benign tumor-like growth of abnormal beta cells in one spot. Diffuse hyperinsulinaemic hypoglycaemia means that beta cells throughout the entire pancreas are affected.^[4]

Before surgery, patients typically undergo specialized imaging called 18F-DOPA PET-CT scanning. This advanced scan uses a radioactive tracer that is taken up by pancreatic beta cells. In focal disease, the scan shows a “hot spot” where the abnormal cells are concentrated, helping surgeons pinpoint exactly where to operate. In diffuse disease, the tracer is distributed evenly throughout the pancreas.^[8]

For focal hyperinsulinaemic hypoglycaemia, the treatment is surgical removal of only the affected area of the pancreas, called a partial pancreatectomy. This can often be done using minimally invasive laparoscopic techniques, where surgeons make small incisions and use specialized instruments guided by cameras. Removing just the focal lesion is usually curative, meaning the patient’s blood sugar returns to normal and medications can be stopped. The rest of the pancreas continues to work normally, so there is little risk of developing diabetes later.^[12]

Diffuse hyperinsulinaemic hypoglycaemia is much more challenging to treat surgically because the problem affects the entire pancreas. In these cases, doctors may recommend a near-total pancreatectomy, which means removing 95 to 98 percent of the pancreas. The small amount of pancreas that is left behind may be enough to produce some insulin and digestive enzymes, but often it is not. Many patients who undergo near-total pancreatectomy develop insulin-dependent diabetes afterward because not enough beta cells remain to produce adequate insulin. They will need to take insulin injections for the rest of their lives. Additionally, removing most of the pancreas can lead to problems with digestion because the pancreas makes enzymes needed to break down food, so patients may need to take enzyme supplements.^[9]

Because of these serious consequences, surgery for diffuse disease is only considered when medical treatment has clearly failed and the patient continues to have dangerous episodes of low blood sugar despite maximum medication doses. The decision to proceed with near-total pancreatectomy involves careful discussion between doctors and families, weighing the risk of ongoing brain damage from hypoglycaemia against the certainty of developing diabetes from surgery.^[1]

Managing Treatment and Follow-Up Care

Regardless of whether treatment involves medications, surgery, or a combination of both, long-term monitoring is essential. Patients need regular blood sugar testing to ensure levels stay within the safe range. Parents of children with hyperinsulinaemic hypoglycaemia are often taught to check blood sugar at home using a glucometer, especially before meals and if the child shows any signs of low blood sugar such as shakiness, sweating, pale skin, or unusual behavior.^[7]

Some children benefit from wearing a continuous glucose monitor, a small device that checks blood sugar levels constantly throughout the day and night. These devices can alert parents and caregivers when blood sugar is dropping, allowing them to take action before a dangerous low occurs. This technology has greatly improved the ability to keep children safe, particularly overnight when hypoglycaemia might otherwise go unnoticed.^[5]

As children with hyperinsulinaemic hypoglycaemia grow, their condition may change. Some forms of the disease, particularly those related to temporary factors like maternal diabetes or prematurity, improve over time. After several months of good blood sugar control on medication, doctors may attempt to gradually reduce medication doses to see if the child can maintain normal glucose levels on their own. This process, called weaning, must be done carefully with close monitoring. If blood sugar remains stable without medication for an extended period, the child may be considered cured.^[6]

Other children, especially those with genetic forms of the condition, may need treatment for many years or even throughout their lives. Regular follow-up with a pediatric endocrinologist (a doctor specializing in hormone problems in children) is important to adjust medications, monitor growth and development, and watch for any complications. Children who have had surgery also need ongoing care to manage diabetes if it develops and to ensure they are receiving adequate pancreatic enzyme replacement if needed.^[12]

Nutritional support is often coordinated with a dietitian who has experience with hyperinsulinaemic hypoglycaemia. The dietitian can help families plan meals and snacks that provide steady glucose without causing blood sugar to spike too high. They can also provide guidance on using cornstarch supplements and managing feeding tubes if these are part of the treatment plan.^[6]

Genetic counseling is recommended for families affected by congenital hyperinsulinaemic hypoglycaemia. Since many forms are inherited, genetic testing can identify the specific mutation responsible. This information helps predict how the disease will behave, guides treatment decisions, and provides families with information about the risk of the condition occurring in future children. In some cases, prenatal testing or preimplantation genetic diagnosis may be options for families planning future pregnancies.^[4]

Most Common Treatment Methods

• Immediate Glucose Replacement
  • Intravenous dextrose given immediately when blood sugar drops below safe levels, often at very high rates of 15 to 30 mg/kg/min to prevent brain damage
  • Oral glucose tablets, gels, or sugary drinks for milder episodes when the patient is conscious and able to swallow
  • Continuous glucose infusions through a vein or feeding tube for patients who cannot maintain safe blood sugar levels between feedings
• Diazoxide Therapy
  • First-line oral medication that opens potassium channels in pancreatic beta cells to reduce insulin secretion
  • Typical doses range from 5 to 15 mg/kg/day, sometimes up to 20 mg/kg/day, divided into two or three doses
  • Treatment duration can last months to years until the condition improves or resolves
  • Does not work in patients with KATP channel mutations (ABCC8 or KCNJ11 genes)
  • Side effects include fluid retention, increased hair growth, and stomach upset
• Somatostatin Analogues
  • Octreotide given by injection or continuous pump at doses of 5 to 25 mcg/kg/day when diazoxide fails
  • Lanreotide given as monthly injection at doses of 30 to 120 mg per month for longer-acting effect
  • Work by inhibiting insulin release from beta cells but can become less effective over time due to receptor downregulation
  • Side effects include stomach problems, and serious risk of necrotizing enterocolitis in newborns
  • Potential for growth deceleration with long-term use, though uncommon if stopped appropriately
• Calcium Channel Blockers
  • Nifedipine used at doses of 0.5 to 2 mg/kg/day when other medications are not suitable
  • Blocks calcium channels involved in triggering insulin release
  • Less effective than diazoxide or somatostatin analogues but may help some patients
  • Side effects include low blood pressure, flushing, and headaches
• Glucagon Treatment
  • Emergency hormone injection that raises blood sugar by triggering glucose release from the liver
  • Can be given as single doses for acute episodes or as continuous infusion through a pump
  • Not a long-term solution as effectiveness decreases with repeated use
  • Side effects include nausea and vomiting
• Experimental Medications in Clinical Trials
  • Sirolimus (rapamycin), an mTOR inhibitor, showing promise in diazoxide-unresponsive patients by blocking overactive cellular pathways in beta cells
  • Newer selective somatostatin analogues targeting specific receptors to reduce side effects
  • GLP-1 receptor antagonists being tested for post-meal hypoglycaemia
  • These treatments are in various phases of clinical trials at specialized centers in the UK, US, and Europe
• Surgical Interventions
  • Partial pancreatectomy for focal disease, removing only the abnormal area of pancreas after localization with 18F-DOPA PET-CT scan, often curative
  • Near-total pancreatectomy (removing 95-98% of pancreas) for severe diffuse disease unresponsive to medications
  • Laparoscopic techniques when possible to minimize surgical trauma and recovery time
  • Risk of developing insulin-dependent diabetes after near-total pancreatectomy
  • Need for pancreatic enzyme replacement after extensive pancreas removal
• Nutritional Management
  • Frequent feedings, sometimes every 2 to 3 hours, to maintain stable blood glucose
  • Continuous overnight feeding through gastrostomy tube (stomach tube) to prevent dangerous nighttime lows
  • Uncooked cornstarch supplements that release glucose slowly over several hours
  • High-carbohydrate meals and snacks planned with a dietitian
• Monitoring and Technology
  • Continuous glucose monitoring devices that alert to dropping blood sugar levels
  • Regular home blood sugar testing with glucometers before meals and when symptoms occur
  • Blood tests to monitor medication levels and detect side effects
  • Regular follow-up with pediatric endocrinologists to adjust treatment