The goal for treatment of GSD type 0 is to avoid hypoglycemia. This is accomplished by avoiding fasting by eating every 3-4 hours during the day. At night, uncooked corn starch can be given because it is a complex glucose polymer. This will be acted on slowly by pancreatic amylase and glucose will be absorbed over a 6 hour period.

Intake of carbohydrates which must be converted to G6P to be utilized (e.g., galactose and fructose) should be minimized. Although elemental formulas are available for infants, many foods contain fructose or galactose in the forms of sucrose or lactose. Adherence becomes a contentious treatment issue after infancy.

Persistent elevation of uric acid above 6.5 mg/dl warrants treatment with allopurinol to prevent uric acid deposition in kidneys and joints.

Because of the potential for impaired platelet function, coagulation ability should be checked and the metabolic state normalized before surgery. Bleeding time may be normalized with 1–2 days of glucose loading, and improved with ddavp. During surgery, iv fluids should contain 10% dextrose and no lactate.

A patient with GSD, type 1b was treated with a liver transplant at UCSF Medical Center in 1993 that resulted in the resolution of hypoglycemic episodes and the need for the patient to stay away from natural sources of sugar. Other patients have undergone this procedure as well with positive results. Although a liver transplant resulted in the resolution of hypoglycemia it did not however resolve the chronic neutropenia and the risk of infection among patients.

Treatment for glycogen storage disease type III may involve a high-protein diet, in order to facilitate gluconeogenesis. Additionally the individual may need:

- IV glucose (if oral route is inadvisable)

- Nutritional specialist

- Vitamin D (for osteoporosis/secondary complication)

- Hepatic transplant (if complication occurs)

Once ketotic hypoglycemia is suspected and other conditions excluded, appropriate treatment reduces the frequency and duration of episodes. Extended fasts should be avoided. The child should be given a bedtime snack of carbohydrates (e.g. spaghetti or pasta or milk) and should be awakened and fed after the usual duration of sleep. If the child is underweight, a daily nutritional supplement may be recommended. Raw cornstarch dissolved in a beverage helps individuals with hypoglycemia, especially that caused by Glycogen Storage Disease, sustain their blood sugars for longer periods of time and may be given at bedtime.

If a spell begins, carbohydrates and fluids should be given promptly. If vomiting prevents this, the child should be taken to the local emergency department for a few hours of intravenous saline and dextrose. This treatment is often expedited by supplying the parents with a letter describing the condition and recommended treatment.

To treat people with a deficiency of this enzyme, they must avoid needing gluconeogenesis to make glucose. This can be accomplished by not fasting for long periods, and eating high-carbohydrate food. They should avoid fructose containing foods (as well as sucrose which breaks down to fructose).

As with all single-gene metabolic disorders, there is always hope for genetic therapy, inserting a healthy copy of the gene into existing liver cells.

The management of Glycogen storage disease IX requires treatment of symptoms by frequent intake of complex carbohydrates and protein to combat the low blood sugar. A nutritionist will advise on suitable diets. Liver function is regularly monitored and problems managed as they arise. However, liver problems have only been successfully treated by a transplant. Routine checks of metabolism are needed to ensure blood sugar (glucose) and ketones are managed. Regular moderate exercise is beneficial, although over-vigorous exercise is to be avoided, especially in those with enlarged livers.

For most horses, diet has a significant impact on the degree of clinical signs. PSSM horses fed diets high in nonstructural carbohydrates (NSC), which stimulate insulin secretion, have been shown to have increased severity of rhabdomyolysis with exercise. Current recommendations for horses with PSSM include a low-starch, high-fat diet. Low-starch diets produce low blood glucose and insulin levels after eating, which may reduce the amount of glucose taken up by the muscle cells. High fat diets increase free fatty acid concentrations in the blood, which may promote the use of fat for energy (via free fatty acid oxidation) over glucose metabolism. Horses with the most severe clinical signs often show the greatest improvement on the diet.

Dietary recommendations usually include a combination of calorie restriction, reduction of daily NSC content, and an increase in dietary fat. Diet recommendations need to be balanced with the animal's body condition score and exercise level, as it may be beneficial to wait on increasing dietary fat after an obese animal has lost weight. The diet should have <10% of digestible energy coming from NSC, and 15-20% of daily digestible energy coming from fat.

Ketosis is deliberately induced by use of a ketogenic diet as a medical intervention in cases of intractable epilepsy. Other uses of low-carbohydrate diets remain controversial. Carbohydrate deprivation to the point of ketosis has been argued to have both negative and positive effects on health.

There is no cure for GALT deficiency, in the most severely affected patients, treatment involves a galactose free diet for life. Early identification and implementation of a modified diet greatly improves the outcome for patients. The extent of residual GALT enzyme activity determines the degree of dietary restriction. Patients with higher levels of residual enzyme activity can typically tolerate higher levels of galactose in their diets. As patients get older, dietary restriction is often relaxed. With the increased identification of patients and their improving outcomes, the management of patients with galactosemia in adulthood is still being understood.

After diagnosis, patients are often supplemented with calcium and vitamin D3. Long-term manifestations of the disease including ovarian failure in females, ataxia. and growth delays are not fully understood. Routine monitoring of patients with GALT deficiency includes determining metabolite levels (galactose 1-phosphate in red blood cells and galactitol in urine) to measure the effectiveness of and adherence to dietary therapy, ophthalmologic examination for the detection of cataracts and assessment of speech, with the possibility of speech therapy if developmental verbal dyspraxia is evident.

Treatment is depended on the type of glycogen storage disease. E.g. GSD I is typically treated with frequent small meals of carbohydrates and cornstarch to prevent low blood sugar, while other treatments may include allopurinol and human granulocyte colony stimulating factor.

Low-protein food is recommended for this disorder, which requires food products low in particular types of amino acids (e.g., methionine).

Children "outgrow" ketotic hypoglycemia, presumably because fasting tolerance improves as body mass increases. In most the episodes become milder and more infrequent by 4 to 5 years of age and rarely occur after age 9. Onset of hypoglycemia with ketosis after age 5 or persistence after age 7 should elicit referral and an intensive search for a more specific disease.

No specific cure has been discovered for homocystinuria; however, many people are treated using high doses of vitamin B (also known as pyridoxine). Slightly less than 50% respond to this treatment and need to take supplemental vitamin B for the rest of their lives. Those who do not respond require a Low-sulfur diet (especially monitoring methionine), and most will need treatment with trimethylglycine. A normal dose of folic acid supplement and occasionally adding cysteine to the diet can be helpful, as glutathione is synthesized from cysteine (so adding cysteine can be important to reduce oxidative stress).

Betaine (N,N,N-trimethylglycine) is used to reduce concentrations of homocysteine by promoting the conversion of homocysteine back to methionine, i.e., increasing flux through the re-methylation pathway independent of folate derivatives (which is mainly active in the liver and in the kidneys).The re-formed methionine is then gradually removed by incorporation into body protein. The methionine that is not converted into protein is converted to S-adenosyl-methionine which goes on to form homocysteine again. Betaine is, therefore, only effective if the quantity of methionine to be removed is small. Hence treatment includes both betaine and a diet low in methionine. In classical homocystinuria (CBS, or cystathione beta synthase deficiency), the plasma methionine level usually increases above the normal range of 30 micromoles/L and the concentrations should be monitored as potentially toxic levels (more than 400 micromoles/L) may be reached.

Supervised exercise programs have been shown in small studies to improve exercise capacity by several measures.

Oral sucrose treatment (for example a sports drink with 75 grams of sucrose in 660 ml.) taken 30 minutes prior to exercise has been shown to help improve exercise tolerance including a lower heart rate and lower perceived level of exertion compared with placebo.

It is important for MADD patients to maintain strength and fitness without exercising or working to exhaustion. Learning this balance may be more difficult than normally, as muscle pain and fatigue may be perceived differently from normal individuals.

Symptomatic relief from the effects of MADD may sometimes be achieved by administering ribose orally at a dose of approximately 10 grams per 100 pounds (0.2 g/kg) of body weight per day, and exercise modulation as appropriate. Taken hourly, ribose provides a direct but limited source of energy for the cells. Patients with myoadenylate deaminase deficiency do not retain ribose during heavy exercise, so supplementation may be required to rebuild levels of ATP.

Creatine monohydrate could also be helpful for AMPD patients, as it provides an alternative source of energy for anaerobic muscle tissue and was found to be helpful in the treatment of other, unrelated muscular myopathies.

To relieve reactive hypoglycemia, the NIH recommends taking the following steps:

- Avoiding or limiting sugar intake;

- Exercising regularly; exercise increases sugar uptake which decreases excessive insulin release

- Eating a variety of foods, including meat, poultry, fish, or nonmeat sources of protein, foods such as whole-grains, fruits, nuts, vegetables, and dairy products;

- Choosing high-fiber foods.

Other tips to prevent sugar crashes include:

- Avoiding eating meals or snacks composed entirely of carbohydrates; simultaneously ingest fats and proteins, which have slower rates of absorption.

- Consistently choosing longer lasting, complex carbohydrates to prevent rapid blood-sugar dips in the event that one does consume a disproportionately large amount of carbohydrates with a meal

- Monitoring any effects medication may have on symptoms.

Low-carbohydrate diet and/or frequent small split meals is the first treatment of this condition. The first important point is to add small meals at the middle of the morning and of the afternoon, when glycemia would start to decrease. If adequate composition of the meal is found, the fall in blood glucose is thus prevented. Patients should avoid rapidly absorbable sugars and thus avoid popular soft drinks rich in glucose or sucrose. They should also be cautious with drinks associating sugar and alcohol, mainly in the fasting state.

As it is a short-term ailment, a sugar crash does not usually require medical intervention in most people. The most important factors to consider when addressing this issue are the composition and timing of foods.

Acute low blood sugar symptoms are best treated by consuming small amounts of sweet foods, so as to regain balance in the body’s carbohydrate metabolism. Suggestions include sugary foods that are quickly digested, such as:

- Dried fruit

- Soft drinks

- Juice

- Sugar as sweets, tablets or cubes.

The main treatments for CTLN1 include a low-protein, high-calorie diet with amino acid supplements, particularly arginine. The Ucyclyd protocol, using buphenyl and ammonul, is used for treatment as well. Hyperammonemia is treated with hemodialysis; intravenous arginine, sodium benzoate, and sodium phenylacetate. In some cases, liver transplantation may be a viable treatment. L-carnitine is used in some treatment protocols.

Individuals presenting with Type III galactosemia must consume a lactose- and galactose-restricted diet devoid of dairy products and mucilaginous plants. Dietary restriction is the only current treatment available for GALE deficiency. As glycoprotein and glycolipid metabolism generate endogenous galactose, however, Type III galactosemia may not be resolved solely through dietary restriction.

Treatment of some forms of hypoglycemia, such as in diabetes, involves immediately raising the blood sugar to normal through the ingestion of carbohydrates, determining the cause, and taking measures to hopefully prevent future episodes. However, this treatment is not optimal in other forms such as reactive hypoglycemia, where rapid carbohydrate ingestion may lead to a further hypoglycemic episode.

Blood glucose can be raised to normal within minutes by taking (or receiving) 10–20 grams of carbohydrate. It can be taken as food or drink if the person is conscious and able to swallow. This amount of carbohydrate is contained in about 3–4 ounces (100–120 ml) of orange, apple, or grape juice although fruit juices contain a higher proportion of fructose which is more slowly metabolized than pure dextrose, alternatively, about 4–5 ounces (120–150 ml) of regular (non-diet) soda may also work, as will about one slice of bread, about 4 crackers, or about 1 serving of most starchy foods. Starch is quickly digested to glucose (unless the person is taking acarbose), but adding fat or protein retards digestion. Symptoms should begin to improve within 5 minutes, though full recovery may take 10–20 minutes. Overfeeding does not speed recovery and if the person has diabetes will simply produce hyperglycemia afterwards. A mnemonic used by the American Diabetes Association and others is the "rule of 15" – consuming 15 grams of carbohydrate followed by a 15-minute wait, repeated if glucose remains low (variable by individual, sometimes 70 mg/dl).

If a person is suffering such severe effects of hypoglycemia that they cannot (due to combativeness) or should not (due to seizures or unconsciousness) be given anything by mouth, medical personnel such as paramedics, or in-hospital personnel can establish IV access and give intravenous dextrose, concentrations varying depending on age (infants are given 2 ml/kg dextrose 10%, children are given dextrose 25%, and adults are given dextrose 50%). Care must be taken in giving these solutions because they can cause skin necrosis if the IV is infiltrated, sclerosis of veins, and many other fluid and electrolyte disturbances if administered incorrectly. If IV access cannot be established, the patient can be given 1 to 2 milligrams of glucagon in an intramuscular injection. More treatment information can be found in the article diabetic hypoglycemia. If a person is suffering less severe effects, and is conscious with the ability to swallow, medical personal such as EMT-B's may administer gelatinous oral glucose.

One situation where starch may be less effective than glucose or sucrose is when a person is taking acarbose. Since acarbose and other alpha-glucosidase inhibitors prevents starch and other sugars from being broken down into monosaccharides that can be absorbed by the body, patients taking these medications should consume monosaccharide-containing foods such as glucose tablets, honey, or juice to reverse hypoglycemia.

Horses with PSSM show fewer clinical signs if their exercise is slowly increased over time (i.e. they are slowly conditioned). Additionally, they are much more likely to develop muscle stiffness and rhabdomyolysis if they are exercised after prolonged stall rest.

Horses generally have fewer clinical signs when asked to perform short bouts of work at maximal activity level (aerobic exercise), although they have difficulty achieving maximal speed and tire faster than unaffected horses. They have more muscle damage when asked to perform lower intensity activity over a longer period of time (aerobic activity), due to an energy deficit in the muscle.

The most effective means of preventing further episodes of hypoglycemia depends on the cause.

The risk of further episodes of diabetic hypoglycemia can often (but not always) be reduced by lowering the dose of insulin or other medications, or by more meticulous attention to blood sugar balance during unusual hours, higher levels of exercise, or decreasing alcohol intake.

Many of the inborn errors of metabolism require avoidance or shortening of fasting intervals, or extra carbohydrates. For the more severe disorders, such as type 1 glycogen storage disease, this may be supplied in the form of cornstarch every few hours or by continuous gastric infusion.

Several treatments are used for hyperinsulinemic hypoglycemia, depending on the exact form and severity. Some forms of congenital hyperinsulinism respond to diazoxide or octreotide. Surgical removal of the overactive part of the pancreas is curative with minimal risk when hyperinsulinism is focal or due to a benign insulin-producing tumor of the pancreas. When congenital hyperinsulinism is diffuse and refractory to medications, near-total pancreatectomy may be the treatment of last resort, but in this condition is less consistently effective and fraught with more complications.

Hypoglycemia due to hormone deficiencies such as hypopituitarism or adrenal insufficiency usually ceases when the appropriate hormone is replaced.

Hypoglycemia due to dumping syndrome and other post-surgical conditions is best dealt with by altering diet. Including fat and protein with carbohydrates may slow digestion and reduce early insulin secretion. Some forms of this respond to treatment with a glucosidase inhibitor, which slows starch digestion.

Reactive hypoglycemia with demonstrably low blood glucose levels is most often a predictable nuisance which can be avoided by consuming fat and protein with carbohydrates, by adding morning or afternoon snacks, and reducing alcohol intake.

Idiopathic postprandial syndrome without demonstrably low glucose levels at the time of symptoms can be more of a management challenge. Many people find improvement by changing eating patterns (smaller meals, avoiding excessive sugar, mixed meals rather than carbohydrates by themselves), reducing intake of stimulants such as caffeine, or by making lifestyle changes to reduce stress. See the following section of this article.

Some clinicians regard eliminating carbohydrates as unhealthy and dangerous. However, it is not necessary to eliminate carbohydrates from the diet completely to achieve ketosis. Other clinicians regard ketosis as a safe biochemical process that occurs during the fat-burning state. Ketosis, which is accompanied by gluconeogenesis (the creation of glucose de novo from pyruvate), is the specific state that concerns some clinicians. However, it is unlikely for a normally functioning person to reach life-threatening levels of ketosis, defined as serum beta-hydroxybutyrate (B-OHB) levels above 15 millimolar (mM) compared to ketogenic diets among non diabetics, which "rarely run serum B-OHB levels above 3 mM." This is avoided with proper basal secretion of pancreatic insulin. People who are unable to secrete basal insulin, such as type 1 diabetics and long-term type II diabetics, are liable to enter an unsafe level of ketosis, eventually resulting in a coma that requires emergency medical treatment. The anti-ketosis conclusions have been challenged by a number of doctors and advocates of low-carbohydrate diets, who dispute assertions that the body has a preference for glucose and that there are dangers associated with ketosis.

Treatment of THB deficiencies consists of THB supplementation (2–20 mg/kg per day) or diet to control blood phenylalanine concentration and replacement therapy with neurotransmitters precursors (L-DOPA and 5-HTP) and supplements of folinic acid in DHPR deficiency.

Tetrahydrobiopterin is available as a tablet for oral administration in the form of "tetrahydrobiopterin dihydrochloride" (BH4*2HCL). BH4*2HCL is FDA approved under the trade name Kuvan. The typical cost of treating a patient with Kuvan is $100,000 per year. BioMarin holds the patent for Kuvan until at least 2024, but Par Pharmaceutical has a right to produce a generic version by 2020. BH4*2HCL is indicated at least in tetrahydrobiopterin deficiency caused by GTPCH deficiency or PTPS deficiency.

Administration of cytidine monophosphate and uridine monophosphate reduces urinary orotic acid and ameliorates the anemia.

Administration of uridine, which is converted to UMP, will bypass the metabolic block and provide the body with a source of pyrimidine.

Uridine triacetate is a drug approved by FDA to be used in the treatment of hereditary orotic aciduria.