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What Drugs Cause Lactic Acidosis?

Lactic Acidosis: Symptoms, Causes, And Treatment

Lactic Acidosis: Symptoms, Causes, And Treatment

Lactic acidosis occurs when the body produces too much lactic acid and cannot metabolize it quickly enough. The condition can be a medical emergency. The onset of lactic acidosis might be rapid and occur within minutes or hours, or gradual, happening over a period of days. The best way to treat lactic acidosis is to find out what has caused it. Untreated lactic acidosis can result in severe and life-threatening complications. In some instances, these can escalate rapidly. It is not necessarily a medical emergency when caused by over-exercising. The prognosis for lactic acidosis will depend on its underlying cause. A blood test is used to diagnose the condition. Lactic acidosis symptoms that may indicate a medical emergency include a rapid heart rate and disorientaiton. Typically, symptoms of lactic acidosis do not stand out as distinct on their own but can be indicative of a variety of health issues. However, some symptoms known to occur in lactic acidosis indicate a medical emergency. Lactic acidosis can occur in people whose kidneys are unable to get rid of excess acid. Even when not related to just a kidney condition, some people's bodies make too much lactic acid and are unable to balance it out. Diabetes increases the risk of developing lactic acidosis. Lactic acidosis may develop in people with type 1 and 2 diabetes mellitus , especially if their diabetes is not well controlled. There have been reports of lactic acidosis in people who take metformin, which is a standard non-insulin medication for treating type 2 diabetes mellitus. However, the incidence is low, with equal to or less than 10 cases per 100,000 patient-years of using the drug, according to a 2014 report in the journal Metabolism. The incidence of lactic acidosis is higher in people with diabetes who Continue reading >>

Lactic Acidosis

Lactic Acidosis

hyperlactaemia: a level from 2 to 5 mmol/L normal production is 20 mmols/kg/day, enters the circulation and undergoes hepatic and renal metabolism (Cori cycle) all tissues can produce lactate under anaerobic conditions lactic acid has a pK value of about 4 so it is fully dissociated into lactate and H+ at body pH (i.e. it is a strong ion) during heavy exercise, the skeletal muscles contribute most of the much increased circulating lactate during pregnancy, the placenta is an important producer of lactate (can pass to fetus as well) major source in sepsis and ARDS is the lung lactate is metabolised predominantly in the liver (60%) and kidney (30%) the heart can also use lactate for ATP production 50% is converted into glucose (gluconeogenesis) and 50% into CO2 and water (citric acid cycle) this results in no net acid accumulation but requires aerobic metabolism the small amount of lactate that is renally filtered (180mmol/day) is fully reabsorbed (ii) impaired hepatic metabolism of lactate (large capacity to clear) clinically there is often a combination of the above to produce a persistent lactic acidosis anaerobic muscular activity (sprinting, generalised convulsions) tissue hypoperfusion (shock, cardiac arrest, regional hypoperfusion -> mesenteric ischaemia) reduced tissue oxygen delivery (hypoxaemia, anaemia) or utilisation (CO poisoning) Type B No Evidence of Inadequate Tissue Oxygen Delivery once documented the cause must be found and treated appropriately D lactate is isomer of lactate produced by intestinal bacterial and not by humans it is not detected on standard lactate assays a bed side test may be able to be developed to help with diagnosis of mesenteric ischaemia venous samples are equivalent to arterial in clinical practice do not need to take off tourniq Continue reading >>

Lactic Acidosis

Lactic Acidosis

Lactic acidosis is a medical condition characterized by the buildup of lactate (especially L-lactate) in the body, which results in an excessively low pH in the bloodstream. It is a form of metabolic acidosis, in which excessive acid accumulates due to a problem with the body's metabolism of lactic acid. Lactic acidosis is typically the result of an underlying acute or chronic medical condition, medication, or poisoning. The symptoms are generally attributable to these underlying causes, but may include nausea, vomiting, rapid deep breathing, and generalised weakness. The diagnosis is made on biochemical analysis of blood (often initially on arterial blood gas samples), and once confirmed, generally prompts an investigation to establish the underlying cause to treat the acidosis. In some situations, hemofiltration (purification of the blood) is temporarily required. In rare chronic forms of lactic acidosis caused by mitochondrial disease, a specific diet or dichloroacetate may be used. The prognosis of lactic acidosis depends largely on the underlying cause; in some situations (such as severe infections), it indicates an increased risk of death. Classification[edit] The Cohen-Woods classification categorizes causes of lactic acidosis as:[1] Type A: Decreased tissue oxygenation (e.g., from decreased blood flow) Type B B1: Underlying diseases (sometimes causing type A) B2: Medication or intoxication B3: Inborn error of metabolism Signs and symptoms[edit] Lactic acidosis is commonly found in people who are unwell, such as those with severe heart and/or lung disease, a severe infection with sepsis, the systemic inflammatory response syndrome due to another cause, severe physical trauma, or severe depletion of body fluids.[2] Symptoms in humans include all those of typical m Continue reading >>

Glyburide And Metformin (oral Route)

Glyburide And Metformin (oral Route)

Precautions Drug information provided by: Micromedex It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly. Blood tests may be needed to check for unwanted effects. Under certain conditions, too much metformin can cause lactic acidosis. The symptoms of lactic acidosis are severe and quick to appear. They usually occur when other health problems not related to the medicine are present and very severe, such as a heart attack or kidney failure. The symptoms of lactic acidosis include abdominal or stomach discomfort; decreased appetite; diarrhea; fast, shallow breathing; a general feeling of discomfort; muscle pain or cramping; and unusual sleepiness, tiredness, or weakness. If you have any symptoms of lactic acidosis, get emergency medical help right away. It is very important to carefully follow any instructions from your health care team about: Alcohol—Drinking alcohol may cause severe low blood sugar. Discuss this with your health care team. Other medicines—Do not take other medicines unless they have been discussed with your doctor. This especially includes nonprescription medicines such as aspirin, and medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems. Counseling—Other family members need to learn how to prevent side effects or help with side effects if they occur. Also, patients with diabetes may need special counseling about diabetes medicine dosing changes that might occur because of lifestyle changes, such as changes in exercise and diet. Furthermore, counseling on contraception and pregnancy may be needed because of the problems that can occur in patients with diabetes during pregnancy. Travel—Keep your recent prescription and your medical history with yo Continue reading >>

Lactic Acidosis: What You Need To Know

Lactic Acidosis: What You Need To Know

Lactic acidosis is a form of metabolic acidosis that begins in the kidneys. People with lactic acidosis have kidneys that are unable to remove excess acid from their body. If lactic acid builds up in the body more quickly than it can be removed, acidity levels in bodily fluids — such as blood — spike. This buildup of acid causes an imbalance in the body’s pH level, which should always be slightly alkaline instead of acidic. There are a few different types of acidosis. Lactic acid buildup occurs when there’s not enough oxygen in the muscles to break down glucose and glycogen. This is called anaerobic metabolism. There are two types of lactic acid: L-lactate and D-lactate. Most forms of lactic acidosis are caused by too much L-lactate. Lactic acidosis has many causes and can often be treated. But if left untreated, it may be life-threatening. The symptoms of lactic acidosis are typical of many health issues. If you experience any of these symptoms, you should contact your doctor immediately. Your doctor can help determine the root cause. Several symptoms of lactic acidosis represent a medical emergency: fruity-smelling breath (a possible indication of a serious complication of diabetes, called ketoacidosis) confusion jaundice (yellowing of the skin or the whites of the eyes) trouble breathing or shallow, rapid breathing If you know or suspect that you have lactic acidosis and have any of these symptoms, call 911 or go to an emergency room right away. Other lactic acidosis symptoms include: exhaustion or extreme fatigue muscle cramps or pain body weakness overall feelings of physical discomfort abdominal pain or discomfort diarrhea decrease in appetite headache rapid heart rate Lactic acidosis has a wide range of underlying causes, including carbon monoxide poisoni Continue reading >>

Hiv & Aids Information :: Factsheet Lactic Acidosis

Hiv & Aids Information :: Factsheet Lactic Acidosis

Please enter the email address. Separate multiple addresses with a comma. Lactic acidosis refers to a build-up of lactic acid in the blood. It is a rare but dangerous side-effect of some anti-HIV drugs most of these are no longer in regular use. Your HIV clinic will use blood tests to check your levels of lactic acid. Lacticacidosis is very rare. Nevertheless, it is an important subject to understandbecause people who develop the condition can become dangerously ill. Lacticacidosis is a serious side-effect of the nucleosidereverse transcriptaseinhibitor (NRTI)class of anti-HIV drugs. This class includes abacavir (Ziagen),didanosine (ddI, Videx), lamivudine (3TC, Epivir), stavudine (d4T,Zerit), tenofovir (Viread) andzidovudine (AZT, Retrovir). The drugsmost linked with lactic acidosis are stavudine and didanosine. However, neitherof these drugs is now used if any other treatment options are available, mainlybecause of the side-effects they can cause. Lactic acidosis is also apotential, but rare, side-effect of other drugs, including the commonlyprescribed diabetes drug, metformin. The term lactic acidosis is used to describehigh levels of a substance called lactate in the blood. Lactate is a by-productof the processing of sugar within the body. Lacticacidosis is one of several conditions which are believed to be caused by damage to mitochondria . Mitochondriaare found in all human cells and are involved in the production of energy.Other possible side-effects ofNRTIs which may also be associated withdamage to mitochondria include peripheral neuropathy (numbness or pain in the feetand hands); bone marrow suppression; pancreatitis (inflammation of thepancreas); hepatic steatosis (accumulation of fat in the liver); and myopathy(muscle damage). "Lactic acidosis may occurat a Continue reading >>

Lactate And Lactic Acidosis

Lactate And Lactic Acidosis

The integrity and function of all cells depend on an adequate supply of oxygen. Severe acute illness is frequently associated with inadequate tissue perfusion and/or reduced amount of oxygen in blood (hypoxemia) leading to tissue hypoxia. If not reversed, tissue hypoxia can rapidly progress to multiorgan failure and death. For this reason a major imperative of critical care is to monitor tissue oxygenation so that timely intervention directed at restoring an adequate supply of oxygen can be implemented. Measurement of blood lactate concentration has traditionally been used to monitor tissue oxygenation, a utility based on the wisdom gleaned over 50 years ago that cells deprived of adequate oxygen produce excessive quantities of lactate. The real-time monitoring of blood lactate concentration necessary in a critical care setting was only made possible by the development of electrode-based lactate biosensors around a decade ago. These biosensors are now incorporated into modern blood gas analyzers and other point-of-care analytical instruments, allowing lactate measurement by non-laboratory staff on a drop (100 L) of blood within a minute or two. Whilst blood lactate concentration is invariably raised in those with significant tissue hypoxia, it can also be raised in a number of conditions not associated with tissue hypoxia. Very often patients with raised blood lactate concentration (hyperlactatemia) also have a reduced blood pH (acidosis). The combination of hyperlactatemia and acidosis is called lactic acidosis. This is the most common cause of metabolic acidosis. The focus of this article is the causes and clinical significance of hyperlactatemia and lactic acidosis. The article begins with a brief overview of normal lactate metabolism. Normal lactate production and Continue reading >>

Lactic Acidosis - Endocrine And Metabolic Disorders - Merck Manuals Professional Edition

Lactic Acidosis - Endocrine And Metabolic Disorders - Merck Manuals Professional Edition

By James L. Lewis, III, MD, Attending Physician, Brookwood Baptist Health and Saint Vincents Ascension Health, Birmingham Lactate is a normal byproduct of glucose and amino acid metabolism. There are 2 main types of lactic acidosis: d-Lactic acidosis (d-lactate encephalopathy) is an unusual form of lactic acidosis. Type A lactic acidosis, the most serious form, occurs when lactic acid is overproduced in ischemic tissueas a byproduct of anaerobic generation of ATP during oxygen deficit. Overproduction typically occurs during global tissue hypoperfusion in hypovolemic, cardiac, or septic shock and is worsened by decreased lactate metabolism in the poorly perfused liver. It may also occur with primary hypoxia due to lung disease and with various hemoglobinopathies. Type B lactic acidosis occurs in states of normal global tissue perfusion (and hence ATP production) and is less ominous. Causes include local tissue hypoxia (eg, as with vigorous muscle use during exertion, seizures, hypothermic shivering), certain systemic and congenital conditions, cancer, and ingestion of certain drugs or toxins (see Table: Causes of Metabolic Acidosis ). Drugs include the nucleoside reverse transcriptase inhibitors and the biguanides phenformin and, less so, metformin; although phenformin has been removed from the market in most of the world, it is still available from China (including as a component of some Chinese proprietary medicines). Metabolism may be decreased due to hepatic insufficiency or thiamin deficiency. d-Lactic acidosis is an unusual form of lactic acidosis in which d-lactic acid, the product of bacterial carbohydrate metabolism in the colon of patients with jejunoileal bypass or intestinal resection, is systemically absorbed. It persists in circulation because human lactat Continue reading >>

Lactic Acidosis: Background, Etiology, Epidemiology

Lactic Acidosis: Background, Etiology, Epidemiology

Author: Kyle J Gunnerson, MD; Chief Editor: Michael R Pinsky, MD, CM, Dr(HC), FCCP, MCCM more... In basic terms, lactic acid is the normal endpoint of the anaerobic breakdown of glucose in the tissues. The lactate exits the cells and is transported to the liver, where it is oxidized back to pyruvate and ultimately converted to glucose via the Cori cycle. In the setting of decreased tissue oxygenation, lactic acid is produced as the anaerobic cycle is utilized for energy production. With a persistent oxygen debt and overwhelming of the body's buffering abilities (whether from chronic dysfunction or excessive production), lactic acidosis ensues. [ 1 , 2 ] (See Etiology.) Lactic acid exists in 2 optical isomeric forms, L-lactate and D-lactate. L-lactate is the most commonly measured level, as it is the only form produced in human metabolism. Its excess represents increased anaerobic metabolism due to tissue hypoperfusion. (See Workup.) D-lactate is a byproduct of bacterial metabolism and may accumulate in patients with short-gut syndrome or in those with a history of gastric bypass or small-bowel resection. [ 3 ] By the turn of the 20th century, many physicians recognized that patients who are critically ill could exhibit metabolic acidosis unaccompanied by elevation of ketones or other measurable anions. In 1925, Clausen identified the accumulation of lactic acid in blood as a cause of acid-base disorder. Several decades later, Huckabee's seminal work firmly established that lactic acidosis frequently accompanies severe illnesses and that tissue hypoperfusion underlies the pathogenesis. In their classic 1976 monograph, Cohen and Woods classified the causes of lactic acidosis according to the presence or absence of adequate tissue oxygenation. (See Presentationand Differe Continue reading >>

Drug-induced Acid-base Disorders

Drug-induced Acid-base Disorders

Abstract The incidence of acid-base disorders (ABDs) is high, especially in hospitalized patients. ABDs are often indicators for severe systemic disorders. In everyday clinical practice, analysis of ABDs must be performed in a standardized manner. Highly sensitive diagnostic tools to distinguish the various ABDs include the anion gap and the serum osmolar gap. Drug-induced ABDs can be classified into five different categories in terms of their pathophysiology: (1) metabolic acidosis caused by acid overload, which may occur through accumulation of acids by endogenous (e.g., lactic acidosis by biguanides, propofol-related syndrome) or exogenous (e.g., glycol-dependant drugs, such as diazepam or salicylates) mechanisms or by decreased renal acid excretion (e.g., distal renal tubular acidosis by amphotericin B, nonsteroidal anti-inflammatory drugs, vitamin D); (2) base loss: proximal renal tubular acidosis by drugs (e.g., ifosfamide, aminoglycosides, carbonic anhydrase inhibitors, antiretrovirals, oxaliplatin or cisplatin) in the context of Fanconi syndrome; (3) alkalosis resulting from acid and/or chloride loss by renal (e.g., diuretics, penicillins, aminoglycosides) or extrarenal (e.g., laxative drugs) mechanisms; (4) exogenous bicarbonate loads: milk–alkali syndrome, overshoot alkalosis after bicarbonate therapy or citrate administration; and (5) respiratory acidosis or alkalosis resulting from drug-induced depression of the respiratory center or neuromuscular impairment (e.g., anesthetics, sedatives) or hyperventilation (e.g., salicylates, epinephrine, nicotine). Notes Continue reading >>

Life Threatening Lactic Acidosis

Life Threatening Lactic Acidosis

M Lemyze, specialist registrar in critical care medicine 1 , J F Baudry, specialist registrar in critical care medicine 2 , F Collet, specialist registrar in critical care medicine 2 , N Guinard, specialist registrar in critical care medicine 2 1Department of Critical Care Medicine, Schaffner Hospital, 62300 Lens, France 2Department of Critical Care Medicine, Broussais Hospital, 35400 Saint Malo, France Correspondence to: M Lemyze malcolmlemyze{at}yahoo.fr An 83 year old woman with diabetes presented to the emergency department with progressive shortness of breath and a two week history of diarrhoea. Her drugs included aspirin, 75 mg four times a day; a combination of irbesartan with hydrochlorothiazide, 300/25 mg four times a day; and metformin, 1000 mg three times a day. She had no previously known renal insufficiency, but on arrival she was oliguric, disoriented, and confused. Her respiratory rate was 32 breaths/min, blood pressure was 76/46 mm Hg, heart rate was 125 beats/min, and rectal temperature reached 36.8C. She had cool and clammy extremities and a persistent skinfoldadditional evidence of severe dehydration. Arterial blood gases showed a profound lactic acidosis, with pH 6.72, partial pressure of carbon dioxide (PCO2) 14 mm Hg, partial pressure of oxygen (PO2) 106 mm Hg, bicarbonate 12 mmol/l, and a high lactate concentration of 17.4 mmol/l. Laboratory results showed a normal blood glucose concentration of 9 mmol/l, a serum urea of 22 mmol/l, a serum creatinine of 779 mol/l, an increased serum potassium concentration of 6.8 mmol/l, and a decreased prothrombin activity of 43% (prothrombin time of 21 seconds). Chest and abdominal examination, chest radiography, urine dipstick, plasma C reactive protein (<5 mg/l), and procalcitonin (<0.5 g/l) concentrations sh Continue reading >>

What Drugs Can Cause Lactic Acidosis?

What Drugs Can Cause Lactic Acidosis?

Some drugs, including metformin, a drug used to treat diabetes, and all nucleoside reverse transcriptase inhibitor drugs used to treat HIV/AIDS can cause lactic acidosis. If you are on any of these medications and have any symptoms of lactic acidosis, get medical help immediately. Anderson, L. , October 2013. Mayo Clinical Proceedings Andrews, M. , May 28, 2002. Scientific American Cairns, SP. ; 2006. Sports Medicine Aaron Mares, MD, University of Pittsburgh Medical Center. Mayo Clinic: "Drugs and Supplements, Glyburide and Metformin (Oral Route): Precautions." NIH: "Side Effects of HIV Medications: HIV and Lactic Acidosis." Pyne, D. , May 2000. European Journal of Applied Physiology Robergs, RA. , September 2004. American Journal of Physiology - Regulatory, Integrative and Comparative Physiology Roth, S. , January 23, 2006. Scientific American Gilbert Willett, PhD, University of Nebraska Medical Center College of Medicine. Reviewed by William Blahd on July 14, 2017 Anderson, L. , October 2013. Mayo Clinical Proceedings Andrews, M. , May 28, 2002. Scientific American Cairns, SP. ; 2006. Sports Medicine Aaron Mares, MD, University of Pittsburgh Medical Center. Mayo Clinic: "Drugs and Supplements, Glyburide and Metformin (Oral Route): Precautions." NIH: "Side Effects of HIV Medications: HIV and Lactic Acidosis." Pyne, D. , May 2000. European Journal of Applied Physiology Robergs, RA. , September 2004. American Journal of Physiology - Regulatory, Integrative and Comparative Physiology Roth, S. , January 23, 2006. Scientific American Gilbert Willett, PhD, University of Nebraska Medical Center College of Medicine. THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for general informational purposes only and does not address individual circumstances. It is not a subst Continue reading >>

Causes Of Lactic Acidosis | Deranged Physiology

Causes Of Lactic Acidosis | Deranged Physiology

A discussion of the causes of a high anion gap metabolic acidosis are frequently required by the CICM SAQs, and lactate often comes up as a differential. Beyond that, there are a series of questions which ask specifically about the causes of lactic acidosis. These questions are numerous. There is practically one in every paper. Question 4.1 from the first paper of 2016 Question 3.3 from the second paper of 2015 Question 27 from the second paper of 2014 Question 23 from the second paper of 2013 Question 26.4 from the second paper of 2013 Question 28 from the second paper of 2012 Question 9.1 from the first paper of 2011 Question 15.3 from the second paper of 2009 Question 3.3 from the second paper of 2009 Many of these questions for some reason focus repetitively on the plight of a certain middle-aged diabetic with a history of alcohol abuse. A specific feature of these questions is the use of red cell transketolase as a test of thiamine deficiency, reminding the candidates that this is an important differential. Lactic acidosis is discussed at greater length in a series of chapters dedicated to acid-base disturbances in their various forms and permutations. In order to simplify revision, a tabulated list of aetiologies is offered below, organised according to an increasingly irrelevant classification system from the 1980s. The massively flawed Cohen-Woods classification Type A lactic acidosis: impaired tissue oxygenation Type B1 lactic acidosis, due to a disease state NRTIs (nucleoside reverse transcriptase inhibitors) Continue reading >>

Drug-induced Metabolic Acidosis

Drug-induced Metabolic Acidosis

Go to: Introduction Metabolic acidosis is defined as an excessive accumulation of non-volatile acid manifested as a primary reduction in serum bicarbonate concentration in the body associated with low plasma pH. Certain conditions may exist with other acid-base disorders such as metabolic alkalosis and respiratory acidosis/alkalosis 1. Humans possess homeostatic mechanisms that maintain acid-base balance ( Figure 1). One utilizes both bicarbonate and non-bicarbonate buffers in both the intracellular and the extracellular milieu in the immediate defense against volatile (mainly CO 2) and non-volatile (organic and inorganic) acids before excretion by the lungs and kidneys, respectively. Renal excretion of non-volatile acid is the definitive solution after temporary buffering. This is an intricate and highly efficient homeostatic system. Derangements in over-production, under-excretion, or both can potentially lead to accumulation of excess acid resulting in metabolic acidosis ( Figure 1). Drug-induced metabolic acidosis is often mild, but in rare cases it can be severe or even fatal. Not only should physicians be keenly aware of this potential iatrogenic complication but they should also be fully engaged in understanding the pathophysiological mechanisms. Metabolic acidosis resulting from drugs and/or ingestion of toxic chemicals can be grouped into four general categories ( Figure 2): Some medications cannot be placed into one single category, as they possess multiple mechanisms that can cause metabolic acidosis. In suspected drug-induced metabolic acidosis, clinicians should establish the biochemical diagnosis of metabolic acidosis along with the evaluation of respiratory compensation and whether there is presence of mixed acid-based disorders 2, then convert the bioche Continue reading >>

Causes Of Lactic Acidosis

Causes Of Lactic Acidosis

INTRODUCTION AND DEFINITION Lactate levels greater than 2 mmol/L represent hyperlactatemia, whereas lactic acidosis is generally defined as a serum lactate concentration above 4 mmol/L. Lactic acidosis is the most common cause of metabolic acidosis in hospitalized patients. Although the acidosis is usually associated with an elevated anion gap, moderately increased lactate levels can be observed with a normal anion gap (especially if hypoalbuminemia exists and the anion gap is not appropriately corrected). When lactic acidosis exists as an isolated acid-base disturbance, the arterial pH is reduced. However, other coexisting disorders can raise the pH into the normal range or even generate an elevated pH. (See "Approach to the adult with metabolic acidosis", section on 'Assessment of the serum anion gap' and "Simple and mixed acid-base disorders".) Lactic acidosis occurs when lactic acid production exceeds lactic acid clearance. The increase in lactate production is usually caused by impaired tissue oxygenation, either from decreased oxygen delivery or a defect in mitochondrial oxygen utilization. (See "Approach to the adult with metabolic acidosis".) The pathophysiology and causes of lactic acidosis will be reviewed here. The possible role of bicarbonate therapy in such patients is discussed separately. (See "Bicarbonate therapy in lactic acidosis".) PATHOPHYSIOLOGY A review of the biochemistry of lactate generation and metabolism is important in understanding the pathogenesis of lactic acidosis [1]. Both overproduction and reduced metabolism of lactate appear to be operative in most patients. Cellular lactate generation is influenced by the "redox state" of the cell. The redox state in the cellular cytoplasm is reflected by the ratio of oxidized and reduced nicotine ad Continue reading >>

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