Uncontrolled Diabetes Symptoms

Uncontrolled diabetes is when your blood sugar levels are consistently above 180 ml/dl or higher. It can lead to life-threatening complications such as diabetic ketoacidosis (DKA), heart attack, or stroke. Chronically high blood sugar levels can damage nerves, blood vessels, and vital organs.

In diabetes, insulin does not shuttle glucose into the cells. When blood sugar accumulates, it becomes toxic to your vital organs, gradually damaging them without your knowledge. In fact, it is estimated that half of the people with diabetes are unaware of their disease and are thus more prone to developing diabetic complications.

The chronic complications of diabetes are broadly divided into two categories:

  • Microvascular: These complications include neuropathy, nephropathy, and retinopathy, which can lead to symptoms of numbness and tingling in the hands, frequent urination, and blurry vision.
  • Macrovascular: These complications consist of cardiovascular disease, stroke, and peripheral artery disease (PAD).

The impact of diabetes doesn’t stop there—other complications that fall outside the two aforementioned categories include dental disease, reduced resistance to infections, and pregnancy and birth complications in women with gestational diabetes.

man standing outside

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Hyperglycemia (High Blood Glucose)

Hyperglycemia—also known as high blood sugar or glucose—is a potentially life-threatening symptom and complication of diabetes that occurs when the body does not produce or properly use insulin.

Hyperglycemia is diagnosed when blood glucose levels are higher than 100 mg/dl while fasting, higher than 180 mg/dl one to two hours after the start of a meal, or when any test shows that your blood glucose level is higher than 200 mg/dl.

Uncontrolled blood sugar has wide-ranging effects. In the early stages of diabetes, few—if any—symptoms are felt, but rare complications can develop over time. Symptoms of hyperglycemia include:

  • Excessive thirst
  • Increased hunger
  • Frequent urination
  • Fatigue
  • Blurry vision

More severe symptoms can include: 

  • Nausea and vomiting
  • Fruity breath (a potential sign of diabetic ketoacidosis) 
  • Rapid breathing
  • Rapid heartbeat
  • Loss of consciousness
hyperglycemia symptoms


Frequent Infections

Uncontrolled high blood glucose can weaken the body's immune system and make it hard for it to fight many different types of infections. High sugar levels in the blood and organs makes it easier for bacteria to grow and infections to develop more quickly.

For example, diabetic foot syndrome has been defined as the presence of foot ulcer associated with neuropathy, PAD, and infection, and it is a major cause of lower limb amputation.

Slow Healing

Slow wound healing in a person with diabetes is the result of lower oxygen delivery to injured areas in the body.

This occurs because the blood vessels may become damaged and narrowed over time, leading to low blood delivery to vital tissues. When you develop a wound, the body tries to repair itself by carrying red blood cells, chemical messengers, and platelets to create new collagen fibers and a clot that forms a scab. If any part of this process is inhibited, it will take longer for the wound to resolve. 

Foot Ulcers

Foot ulcers are common in people with diabetes because a small cut can quickly develop into a larger problem due to slow wound healing. If left untreated, foot ulcers can result in severe complications like:

  • Leg amputation
  • Sepsis
  • Even death

Frequent Urination

If you are waking up multiple times in the middle of the night to use the bathroom or urinating more frequently—and often in larger amounts—than normal, you may be experiencing polyuria.

Polyuria, or frequent urination, is a symptom of diabetes that can lead to extreme dehydration and kidney dysfunction if your blood glucose levels are not kept in check. Polyuria in diabetes occurs when you have excess levels of sugar in the blood.

Normally, when your kidneys create urine, they reabsorb all the sugar and direct it back to the bloodstream, but this does not happen in diabetes. Instead, the excess glucose ends up in the urine, where it pulls more water and results in more urine.

It’s important to remember that the symptom of frequent urination is both relative and subjective to some degree. Some people naturally urinate more than others, and it can be hard to tell if your higher than normal urination pattern is a symptom of diabetes or something else.

Oftentimes the symptom of frequent urination alone is not enough to assume a diagnosis of diabetes, but if you experience frequent urination plus other symptoms like unexplained weight loss, extreme fatigue, blurry vision, or increased thirst, it may be a sign that you have high blood sugar levels and may need to see a healthcare provider to help give you clarity on your situation and potentially avoid serious complications down the line. 

Frequent Thirst

Polydipsia—or frequent or excessive thirst—is commonly found with frequent urination because the kidneys are working on overdrive to excrete excess glucose from the urine.

As previously mentioned, glucose acts as an osmole, which means water follows it out of the body. As a result, you may feel dehydrated, even if you drank plenty of water and other fluids. This feeling is just your body craving what it has lost as a result of your diabetes.

When your body is at a water deficit, it signals to your brain that you need to take in more fluids. In diabetes, drinking more water may help you to feel better in the short term, but it won’t solve the problem. In order to curb your thirst for good, you must appropriately manage your diabetes, via medication, lifestyle changes, or both. 

Extreme dehydration can make your blood sugar levels rise more quickly than normal since less urine—and glucose—are being expelled. Therefore, excessive thirst may also be looked at as a warning sign of diabetes since its symptoms occur in two stages. Beginning symptoms of prolonged dehydration as a result of polydipsia can lead to:

  • Nausea
  • Dizziness
  • Headaches
  • Fainting

More long-term symptoms of dehydration include coma and death. 

Extreme Fatigue

Fatigue is a persistent symptom in those with diabetes, and it may present as an early sign that something is wrong or as one of a constellation of complaints. No matter the case, fatigue is simply having lower than normal energy levels for a period of time.

There is little research on the specific causes of fatigue in people with diabetes, but researchers have developed models that illustrate multiple factors that contribute to fatigue in people with diabetes. Some of the factors that may contribute to fatigue are:

  • Stress (resulting from the diagnosis or management of diabetes)
  • Being overweight or obese
  • Depression
  • Sleep problems
  • Chronic pain
  • Hyperglycemia

Extreme fatigue plays a significant role in the quality of life and should not be overlooked as a symptom of diabetes. Diabetes fatigue syndrome has been shown to impact one’s ability to carry out everyday activities of daily living. It may be caused by a variety of factors, including:

  • Lifestyle
  • Nutrition
  • Medical
  • Psychological
  • Endocrine
  • Drug-related factors

Therefore, adequate management of extreme fatigue usually takes the help of a diabetes care team.

Diabetic Ketoacidosis

Diabetic ketoacidosis (DKA) is a serious and sometimes life-threatening complication that can lead to diabetic coma or death if not treated immediately. DKA most frequently occurs in those with type 1 diabetes, but in rare cases, it may happen in people with type 2 diabetes.

Symptoms develop quickly—usually over 24 hours—and range from nausea or vomiting to extreme fatigue and trouble thinking clearly. DKA is commonly triggered when you are under stress—like being sick—or when taking medications that change how your body handles glucose.

DKA presents with a myriad of vague signs and symptoms, such as nausea, vomiting, and abdominal pain. People with DKA may also have symptoms of polydipsia and polyuria, or increased thirst and urination. Some may also report smelling a fruity odor on their breath, although this is more frequently observed on a physical examination by a healthcare professional.

Severe cases may also be characterized by low blood pressure (hypotension) or difficulty thinking clearly (altered sensorium).

DKA symptoms typically occur as a constellation of warning signs. The first signs include:

  • Increased thirst
  • Frequent urination
  • High blood glucose (blood sugar) levels
  • High levels of ketones in the urine (which is sometimes identified when there is a fruity smell to the urine; you can detect ketones via a urine test using a test strip )

While the second set of signs include:

  • Extreme fatigue
  • Flushed skin
  • Feeling dehydrated (often characterized by dry skin or dry mouth)
  • Nausea
  • Vomiting
  • Abdominal pain 
  • Rapid shallow breathing called Kussmaul breathing
  • Fruity odor on breath
  • A hard time paying attention, or confusion

Although the symptoms of DKA are progressive in nature, it is important to note that there is tremendous overlap between the two groups. It is not entirely uncommon for early symptoms of DKA to be extreme fatigue or dehydration instead of increased thirst or frequent urination.

Constant Hunger

Polyphagia or hyperphagia describes excessive hunger, increased appetite, or even simply eating more than you normally do. It is one of the three main signs of diabetes, along with increased thirst and frequent urination.

The vague symptom of constant hunger can occur for many reasons, such as following a rigorous exercise routine or after marijuana use, but when it is in combination with other symptoms, it may be a sign of something more serious like diabetes, stress, or depression.

When diabetes is uncontrolled, it prevents glucose from the blood from entering the cells, so the body can’t convert the food you eat into energy. This lack of energy signals to your brain that it needs to eat more. Like thirst, eating a meal may help you to feel better in the short term, but it will not get rid of your hungry feeling for good. In fact, it may exacerbate the problem by adding to your already high sugar levels.

In people with uncontrolled diabetes, the best way to lower your blood glucose levels in the short and long term is to:

  • Manage your sugar and carbohydrate intake
  • Participate in routine exercise so your body can stimulate insulin production
  • Reduce blood sugar levels, and take insulin or insulin-regulating medication

If the hunger persists, you may need to consult a healthcare professional or diabetes health specialist.

Blurry Vision

Blurry vision is the inability to see images clearly, and it may be one of the earliest signs of diabetes. It occurs when your blood sugar levels are too high, too low, or rapidly fluctuating.

Chronically high blood glucose levels, or hyperglycemia, can change the shape of the lens in your eye. When your blood glucose levels are too high, fluid builds up in the eye, leading to a change in the shape of the lens, which puts images out of focus, distorting your view. Correction of blurry vision due to hyperglycemia can take up to six weeks after normalizing your blood sugar levels. 

When your blood sugar levels are too low—known as hypoglycemia—your vision may get blurry because your brain is not functioning optimally. Fortunately, a resolution of your hypoglycemia usually resolves your blurry vision.

Blurry vision may happen in one or both eyes. Rapidly changing blood glucose levels may also transiently change your vision, leading to occasional bouts of blurry vision. 

Closely managing your symptoms of diabetes and taking the appropriate steps to control your blood sugars are the best ways to avoid serious vision complications. Uncontrolled blood glucose can lead to damage to the small vessels of the eye. The retinal blood vessels leak blood and fluid into the retina, known as diabetic macular edema, which can contribute to diabetic retinopathy (DR), a condition that causes blurred vision and may eventually lead to vision loss.

Ocular complications associated with diabetes are one of the most significant causes of morbidity and are preventable with early detection and timely treatment. In fact, diabetes is the leading cause of blindness in those ages 20 to 74 in the United States.

If you have diabetes, you may want to consider seeing an optometrist and ophthalmologist regularly, as research has shown that routine ophthalmological checkups can help prevent vision loss. 

Weight Loss

If your blood sugar levels are consistently high, it may lead to your body breaking down muscle and fat for energy, leading to a noticeable loss in muscle mass.

Muscle is heavier than fat, so weight loss is common in those with diabetes. Also, excessive urination means that you are losing water, which may also contribute to your weight fluctuations. 

Fruity Breath

If your breath smells like acetone—or nail polish remover—you may have high levels of ketones in your blood, a sign of impending DKA. DKA is a potentially life-threatening condition that occurs when insulin metabolism is impaired, so the body cannot get energy from glucose. The body burns fat as an alternative energy source, which means it produces ketones as a byproduct.

Fruity breath is a hallmark sign of ketones in the blood. If your diabetes is not controlled quickly, medical complications can occur. Severe symptoms of DKA typically develop over the course of 24 to 48 hours. Classic symptoms include:

  • Nausea
  • Vomiting
  • Lethargy
  • Altered mental status
  • Abdominal pain 

Hearing Problems

Hearing loss is more common in those who have diabetes, but the reasons for this association are unknown.

A recent study found that hearing loss is twice as likely in those with diabetes versus those without diabetes; and of the 88 million adults in the United States who have prediabetes, the rate of hearing loss was 30% higher than in those with normal blood glucose.

Some diabetes researchers theorize that the high blood glucose levels associated with diabetes cause damage to the small blood vessels in the inner ear, similar to the way in which diabetes can damage the eyes and the kidneys. Still, more research needs to be done to elucidate the cause, if any, of hearing loss due to uncontrolled diabetes. 

Circulation Problems

High glucose levels over many years might lead to plaque buildup in the blood vessels, which could make it more difficult for the circulatory system to move oxygen and nutrients throughout the body, especially to the feet and legs. This phenomenon is known as peripheral artery disease (PAD). The risk of PAD is increased in those with diabetes, occurs earlier, and is often more severe.

Poor circulation has wide-ranging effects, as it can cause pain and discomfort, and the lack of consistent blood supply can slow the healing process for cuts or sores. When left untreated, nonhealing cuts can become infected. Over time, poorly managed circulation problems can cause kidney failure and blindness, and in extreme cases may lead to leg or foot amputation.

The symptoms of poor circulation are wide-ranging, but they may not be apparent or associated with your diabetes early on. These symptoms can affect a person’s quality of life and may even cause severe complications.

Common symptoms include:

  • Brittle toenails
  • Chest pain when exercising
  • Hair loss on your legs and feet
  • Numbness and tingling in the hands and feet
  • Cold hands and feet
  • Swelling in the feet, ankles, and legs
  • Memory loss and difficulty concentrating
  • Digestive issues
  • Fatigue
  • Joint and muscle cramping
  • Skin color changes
  • Ulcers in the legs or feet
  • Varicose veins

Skin Disorders

If you have diabetes and skin changes occur, it is likely a sign that your blood glucose levels are too high. This could mean that your treatment for diabetes needs to be adjusted or that you may need to double down on lifestyle changes like weight loss.

Diabetes-Related Skin Conditions

Acanthosis Nigricans

Acanthosis nigricans (AN) is a skin disorder characterized by velvety, raised, darkly pigmented skin lesions found in body folds such as under the armpit, groin, and neck. Those who are obese or diabetic are most likely to present with AN. Type 2 diabetes is often associated with obesity, so AN is more commonly found in this group.

AN develops from the stimulation of growth factors in the skin. Additionally, elevated IGF-1 levels in overweight people can contribute to keratinocyte and fibroblast proliferation.

AN is usually an incidental finding on a physical exam and is relatively benign, although its presence is a warning sign for diabetes or a signal that your diabetes needs to be managed better. Weight loss and proper management of your diabetes can improve the skin condition. Some creams may help to lessen the appearance of the spots as well. 

Diabetic Dermopathy

Diabetes can cause changes in the small blood vessels that are also known as skin spots. These oval or circular, light brown, and scaly patches characterize diabetic dermopathy, and most often occur on the front of both legs. They do not hurt, open up, or itch.

Dermopathy is harmless and doesn't need to be treated.

Necrobiosis Lipoidica Diabeticorum

Necrobiosis lipoidica diabeticorum (NLD) is caused by changes in the blood vessels as a result of uncontrolled diabetes. NLD causes spots similar to diabetic dermopathy, but they are fewer, larger, and deeper. The rash, which usually occurs on the lower legs, starts as a dull, red, raised area and slowly morphs into a shiny scar with a violet border.

The cause of NLD is unknown, but the condition is more common in women. Sometimes NLD is itchy and painful. If the sores do not break open, they usually do not have to be treated, but open sores should be seen by a healthcare professional. Topical cortisone creams have been used with mixed effect.

Allergic Reactions

Insulin or popular blood glucose–regulating drugs like sulfonylureas can cause skin rashes and reactions to the sun. See a healthcare professional if you think you are having a reaction to a medicine, and be on the lookout for rashes, depressions, or bumps at your insulin injection site.

Diabetic Blisters (Bullosis Diabeticorum)

In very rare cases, blisters can form on the backs of fingers, hands, toes, feet, and sometimes on legs or forearms. These sores look like burn blisters and often occur in people who have diabetic neuropathy.

Despite their large size and ominous look, they are often painless. These blisters heal by themselves, usually without scars, in about three weeks. The only treatment is to bring blood sugar levels under control.

Eruptive Xanthomatosis

Uncontrolled diabetes can lead to eruptive xanthomatosis (EX)—firm, yellow, pea-like enlargements of the skin. Each bump has a red halo and may itch. This condition occurs most often on the backs of hands, feet, arms, legs, and buttocks.

Men and those with type 1 diabetes are more likely to experience EX than women and those with type 2 diabetes. Of note, high fat and cholesterol levels may also be found in the blood. Like diabetic blisters, these bumps disappear when diabetes control is restored.

Digital Sclerosis

Digital sclerosis is stiffness of the skin on your toes, fingers, and hands as a result of poor blood flow. The skin can become tight, thick, or waxy, and the impacted areas may no longer move the way they should.

Finger and toe joints are more likely to be impacted than knee, ankle, or elbow joints, but the reason why is unknown. The only treatment is to bring blood sugar levels under control.

Disseminated Granuloma Annulare

Disseminated granuloma annulare (DGA) is usually a self-limited, benign granulomatous disease of the top two layers of the skin—the dermis and subcutaneous tissues. It is associated with underlying diabetes mellitus, and at times it precedes the sign and symptoms of diabetes mellitus

DGA is characterized by sharply defined ring- or arc-shaped raised areas on the skin. These rashes occur most often on the extremities, especially parts of the body that are far away from the trunk like the fingers or ears. They can be red, red-brown, or skin-colored.

Preventing Skin Complications

To prevent skin complications:

  • Keep your diabetes well managed.
  • Practice good skin hygiene, especially foot care.
  • Avoid very hot baths and showers.
  • Use lotion (preventing dry skin is important because you may be more likely to pick at it, opening up the skin and allowing infections to set in).
  • Treat cuts right away.
  • Use mild shampoos.

Talk to your healthcare provider or dermatologist if you are not able to solve a skin problem yourself.

A Word From Verywell

Preventing complications from diabetes is largely the result of managing your blood sugar levels with medication and lifestyle interventions, such as eating a low-carb diet and developing an exercise routine.

Weight loss can also help to reverse the negative health impacts of insulin resistance that are seen in those with type 2 diabetes and even prediabetes. Setting realistic goals can help you stay on track. The goal is not to achieve a perfect weight or blood sugar level; instead, it is to reduce your risk of developing diabetes-related complications by creating a health-positive lifestyle routine that you can stick to.

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