Lantus Overdose: Case Presentation and Management Options

Intentional Insulin Overdose and Depression in Subjects with and Without Diabetes Mellitus: A Commentary

Insulin is an essential medication for people with type 1 diabetes mellitus and for some people with type 2 diabetes. Interestingly, insulin abuse has been reported as a mode of suicide, not only among people with diabetes, but also among their relatives, and among medical and paramedical personnel who have access to insulin. The aim of the present commentary was to raise awareness of potential depression-related intentional insulin overdose and its complications, as well as of the diagnosis and treatment of this entity. Insulin overdose may lead to severe and prolonged hypoglycemia, hypoglycemic coma, and death. Moreover, hypokalemia, hypomagnesemia, hypophosphatemia, and elevated liver enzymes are common. Insulin overdose should be suspected among people with diabetes in case of unexplained prolonged hypoglycemia and among people without diabetes who exhibit hypoglycemia and may have access to diabetic medications. The ratio of insulin to C-peptide helps distinguish exogenous insulin administration from endogenous secretion. The cornerstone of therapy is prompt administration of concentrated glucose infusions for days with simultaneous oral intake, when possible, and intense glucose monitoring to prevent hypoglycemia. Moreover, monitoring of serum electrolyte levels is recommended. Finally, psychiatric evaluation aiming at early identification of depression and suicidality is of paramount importance.

High-Concentration Insulin Glargine Overdose: Polyphasic Patterns of Blood Insulin Levels

In the treatment of diabetes mellitus, there is a growing trend towards using high-concentration insulin, with Lantus XR (Bridgewater, NJ: Sanofi-Aventis U.S. LLC), which has a drug concentration three times higher than that of conventional Lantus (100 U/mL; Bridgewater, NJ: Sanofi-Aventis U.S. LLC), being a prominent example. This type of high-concentration insulin is known for its smaller injection volumes, leading to a slower absorption rate and maintenance of more consistent blood insulin levels. When administered in high doses, the pharmacological effects of insulin are generally prolonged; however, insulin glargine overdose rarely occurs, and its pharmacokinetics remain unclear. We encountered a case of an insulin overdose in a 19-year-old female patient, who had self-injected glargine (Lantus XR) 1,350 units and aspart (NovoRapid; Bagsværd, Denmark: Novo Nordisk A/S) 600 units. We measured blood glucose and insulin levels over time. Bimodal peaks in blood insulin levels were observed, and we adjusted high doses of intravenous infusion with a 50% glucose solution until the blood insulin levels returned to the normal range. Consequently, the patient was treated without inducing severe hypoglycemia. U300 glargine overdose may lead to both a multimodal elevation in blood insulin levels and prolonged hypoglycemia compared to U100 glargine. Therefore, monitoring blood insulin levels and adjusting treatment accordingly may contribute to safer patient management. This study represents the initial documentation of blood insulin levels measured in a U300 glargine overdose patient, revealing a bimodal peak.

The Other Face of Insulin—Overdose and Its Effects

Insulin is the most effective glycemic-lowering drug, and for people suffering from type 1 diabetes it is a life-saving drug. Its self-dosing by patients may be associated with a higher risk of overdose, both accidental and deliberate. Insulin-induced hypoglycemia causes up to 100,000 emergency department calls per year. Cases of suicide attempts using insulin have been described in the literature since its introduction into therapy, and one of the important factors in their occurrence is the very fact of chronic disease. Up to 90% of patients who go to toxicology wards overdose insulin consciously. Patients with diabetes are burdened with a 2–3 times higher risk of developing depression compared to the general population. For this reason, it is necessary to develop an effective system for detecting a predisposition to overdose, including the assessment of the first symptoms of depression in patients with diabetes. A key role is played by a risk-conscious therapeutic team, as well as education. Further post-mortem testing is also needed for material collection and storage, as well as standardization of analytical methods and interpretation of results, which would allow for more effective detection and analysis of intentional overdose—both by the patient and for criminal purposes.

Case Report: High-concentration Insulin Glargine Overdose Complicated by Hepatic Steatosis

The use of high-concentration formulations of insulin is becoming more prevalent in the management of patients with diabetes mellitus. Situations of intentional overdose utilizing these agents pose particular challenges because of the altered pharmacology at large doses and the potential complications arising thereof.

A patient with type 1 diabetes mellitus self-administered 4050 units of high-concentration (300 units/mL) insulin glargine, in addition to coingestants. The patient subsequently required 7 days of high-dose dextrose infusion in order to avoid hypoglycemia, with no further insulin needed during this period. The patient also developed reversible hepatic steatosis secondary to the prolonged use of high-dose dextrose.

Owing to the altered pharmacology of high-concentration insulin glargine when administered at large doses in cases of intentional overdose, patients are likely to require a much longer period of supplemental dextrose support than may otherwise be expected when these agents are used at therapeutic doses. The complication of hepatic injury in the form of steatosis also needs to be considered in these patients, and should prompt the use of adaptive prescriptions of intravenous dextrose where possible.

A Systematic Review on Insulin Overdose Cases: Clinical Course, Complications and Treatment Options

A large overdose of insulin is a serious health matter. Information concerning administration and duration of intravenous (IV) glucose, other treatment options or complications besides hypoglycaemia following large insulin overdoses is not readily apparent from the literature. A systematic search, compilation and review of case reports on insulin overdoses, published 1986-2017, was performed in PubMed, EMBASE, Cochrane and PROSPERO databases. Of 1523 published articles, 45 cases of insulin overdoses were included with a total median insulin dose of 900 international units (IU) (range 26-4800 IU). Hospitalization occurred in 44 cases with a median hospitalization duration of 94 hr (range 12-721 hr), and one-third (n = 15) admitted to the intensive care unit. First-line treatment was IV glucose treatment in 95% of cases. Treatment options besides IV glucose that were reported beneficial included glucagon IV or intramuscular (IM), octreotide IV or IM, surgical excision, hydrocortisone IV and oral intake of complex carbohydrates. Prevalent complications were intermittent cerebral impairment (73%), hypokalaemia (49%), other electrolyte disturbances (42%), and hepatic disturbances (7%) and cardiac toxicity (e.g. cardiac arrhythmia) (9%). Long-term consequences were one case of lasting hypoglycaemic encephalopathy and one death. In conclusion, following large insulin overdoses, in-hospital admission and treatment with IV glucose may be needed for up to a week. Monitoring of electrolytes and hepatic and cardiac functions seems important. Several experimental treatment options may be considered in addition to glucose administration. With appropriate pre- and in-hospital treatment, cases with severe hypoglycaemia and neurologic complications may have a favourable outcome.

Octreotide for the treatment of intentional insulin aspart overdose in a non-diabetic patient

Intentional insulin overdose may lead to severe and refractory hypoglycemia. Exogenous dextrose administration is the mainstay of therapy for these patients and is effective in most cases. However, in patients with a functional pancreas, exogenous dextrose administration may precipitate endogenous insulin release leading to rebound hypoglycemia. We describe a case report of a 41-year-old woman who injected 300 units of insulin aspart with suicidal intent. Her initial blood glucose was 2.3 mmol/L (41 mg/dL). Over the next 12 hours, she experienced recurrent hypoglycemic episodes despite 10% dextrose infusions and 14 ampoules of 50% dextrose. Our patient experienced complications, including peripheral edema, related to the large volumes of intravenous dextrose required to attempt to maintain euglycemia. Octreotide, a somatostatin analogue, may help prevent dextrose-induced hypoglycemia and improve the management in select insulin overdose patients; large infusion volumes resulted in significant peripheral edema. Treatment with octreotide was initiated 12.5 hours post-injection and was followed by a stabilization of blood glucose concentration in this non-diabetic patient.

Insulin glargine overdose

Insulin glargine is a long acting novel recombinant human insulin analogue indicated to improve glycemic control, in adults and children with type 1 diabetes mellitus and in adults with type 2 diabetes mellitus. The time course of action of insulins including insulin glargine may vary between individuals and/or within the same individual. Insulin glargine is given as a 24-h dosing regimen and has no documented half-life or peak effect. Hypoglycemia is the most common adverse effect of insulin, including insulin glargine. As with all insulins, the timing of hypoglycemia may differ among various insulin formulations. We present a case of a 76-year-old male insulin-dependent diabetic patient with refractory hypoglycemia secondary to an intentional overdose of insulin glargine. We would like to highlight the necessity of prolonging IV glucose infusion, for a much longer period than expected from pharmacokinetic properties of these insulin analogues after intentional massive overdose.

Acute hepatic injury following treatment of a long-acting insulin analogue overdose necessitating urgent insulin depot excision

BACKGROUND

A 26-year-old man with Type 1 diabetes presented with an overdose of 4800 units of the long-acting insulin analogue, glargine (Lantus). Glucose supplementation of approximately 800 g/day was associated with acute hepatic injury.

METHODS

On day 4, a depot of insulin was excised from the patient's abdominal wall; this was followed by a reduction in his glucose requirements and improvement in liver function.

CONCLUSIONS

This report highlights the risk of acute hepatic injury during the treatment of insulin overdose and the importance of careful glucose supplementation. It also demonstrates how earlier excision of an insulin depot could potentially prevent this problem and hasten recovery.