Macrogol is the international nonproprietary name used for

polyethylene glycol Polyethylene glycol (PEG; ) is a polyether compound derived from petroleum with many applications, from industrial manufacturing to medicine. PEG is also known as polyethylene oxide (PEO) or polyoxyethylene (POE), depending on its molecular wei ...

(PEG) as a medication ingredient. It is usually followed by a number indicating the average

molecular weight A molecule is a group of two or more atoms that are held together by Force, attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemi ...

, indicating the length of the polymer of the specific molecule in use. Macrogol is used as a

laxative Laxatives, purgatives, or aperients are substances that loosen stools and increase bowel movements. They are used to treat and prevent constipation. Laxatives vary as to how they work and the side effects they may have. Certain stimulant, lubri ...

to treat

constipation Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The Human feces, stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the ...

in children and adults. It is taken

by mouth Oral administration is a route of administration whereby a substance is taken through the Human mouth, mouth, swallowed, and then processed via the digestive system. This is a common route of administration for many medications. Oral administ ...

. Benefits usually occur within three days. It is also used as an

excipient An excipient is a substance formulated alongside the active ingredient of a medication. They may be used to enhance the active ingredient’s therapeutic properties; to facilitate drug absorption; to reduce viscosity; to enhance solubility; to i ...

. It is also used to clear the

bowel The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascular system. T ...

s before a

colonoscopy Colonoscopy () or coloscopy () is a medical procedure involving the Endoscopy, endoscopic examination of the large bowel (colon) and the distal portion of the small bowel. This examination is performed using either a Charge-coupled device, CCD ...

, when the onset of the laxative effect is more rapid, typically within an hour. Side effects may include increased bowel gas, abdominal pain, and nausea. Rare but serious side effects may include an abnormal heartbeat,

seizure A seizure is a sudden, brief disruption of brain activity caused by abnormal, excessive, or synchronous neuronal firing. Depending on the regions of the brain involved, seizures can lead to changes in movement, sensation, behavior, awareness, o ...

s, and

kidney In humans, the kidneys are two reddish-brown bean-shaped blood-filtering organ (anatomy), organs that are a multilobar, multipapillary form of mammalian kidneys, usually without signs of external lobulation. They are located on the left and rig ...

problems. Use appears to be safe during

pregnancy Pregnancy is the time during which one or more offspring gestation, gestates inside a woman's uterus. A multiple birth, multiple pregnancy involves more than one offspring, such as with twins. Conception (biology), Conception usually occurs ...

. It is classified as an

osmotic laxative Laxatives, purgatives, or aperients are substances that loosen stools and increase bowel movements. They are used to treat and prevent constipation. Laxatives vary as to how they work and the side effects they may have. Certain stimulant, lubri ...

: It works by increasing the amount of water in the stool. Macrogol came into use as a bowel prep in 1980 and was approved for medical use in the United States in 1999. It is available as a

generic medication A generic drug is a pharmaceutical drug that contains the same chemical substance as a drug that was originally protected by chemical patents. Generic drugs are allowed for sale after the patents on the original drugs expire. Because the active ch ...

and

over the counter Over-the-counter (OTC) drugs are medicines sold directly to a consumer without a requirement for a prescription from a healthcare professional, as opposed to prescription drugs, which may be supplied only to consumers possessing a valid pres ...

. In 2022, it was the 209th most commonly prescribed medication in the United States, with more than 1million prescriptions. It is also formulated together with

electrolytes An electrolyte is a substance that conducts electricity through the movement of ions, but not through the movement of electrons. This includes most soluble salts, acids, and bases, dissolved in a polar solvent like water. Upon dissolving, t ...

. In 2022, the combination with electrolytes was the 282nd most commonly prescribed medication in the US, with more than 600,000 prescriptions.

Medical uses

Constipation

Macrogol 3350, often in combination with

electrolyte An electrolyte is a substance that conducts electricity through the movement of ions, but not through the movement of electrons. This includes most soluble Salt (chemistry), salts, acids, and Base (chemistry), bases, dissolved in a polar solven ...

s, is used for short-term relief of constipation as well as for long-term use in constipation of various causes, including in people with

multiple sclerosis Multiple sclerosis (MS) is an autoimmune disease resulting in damage to myelinthe insulating covers of nerve cellsin the brain and spinal cord. As a demyelinating disease, MS disrupts the nervous system's ability to Action potential, transmit ...

Parkinson's disease Parkinson's disease (PD), or simply Parkinson's, is a neurodegenerative disease primarily of the central nervous system, affecting both motor system, motor and non-motor systems. Symptoms typically develop gradually and non-motor issues become ...

as well as constipation caused by pharmaceutical drugs such as

opioid Opioids are a class of Drug, drugs that derive from, or mimic, natural substances found in the Papaver somniferum, opium poppy plant. Opioids work on opioid receptors in the brain and other organs to produce a variety of morphine-like effects, ...

s and

anticholinergic Anticholinergics (anticholinergic agents) are substances that block the action of the acetylcholine (ACh) neurotransmitter at synapses in the central nervous system, central and peripheral nervous system. These agents inhibit the parasympatheti ...

s. Whole bowel irrigation with macrogol is part of the bowel preparation before

surgery Surgery is a medical specialty that uses manual and instrumental techniques to diagnose or treat pathological conditions (e.g., trauma, disease, injury, malignancy), to alter bodily functions (e.g., malabsorption created by bariatric surgery s ...

. Limited data also support its use for the treatment of

fecal impaction A fecal impaction or an impacted bowel is a solid, immobile bulk of feces that can develop in the rectum as a result of chronic constipation (a related term is fecal loading which refers to a large volume of stool in the rectum of any consistency ...

. In those with chronic constipation it works better than

lactulose Lactulose is a non-absorbable sugar used in the treatment of constipation and hepatic encephalopathy. It is administered orally for constipation, and either orally or rectally for hepatic encephalopathy. It generally begins working after 8� ...

. Popular types include: macrogol 3350, macrogol 4000, and macrogol 6000. The number represents the

. Combining different molecular weights provides some control over the consistency.

Excipient

Macrogol is used as an

in pharmaceutical products. Lower-molecular-weight variants are used as solvents in oral liquids and soft capsules, whereas solid variants are used as

ointment A topical medication is a medication that is applied to a particular place on or in the body. Most often topical medication means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes ...

bases, tablet binders,

film coating A film coating is a thin polymer-based coat that is typically sprayed onto solid pharmaceutical dosage forms, such as Tablet (pharmacy), tablets, Capsule (pharmacy), capsules, pellets or granules. Film coating can impact both its appearance and i ...

s, and

lubricant A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, ...

s. For example, PEG-2000 is one of the excipients in the

Moderna COVID-19 vaccine The Moderna COVID19 vaccine, sold under the brand name Spikevax, is a COVID-19 vaccine developed by the American company Moderna, the United States National Institute of Allergy and Infectious Diseases (NIAID), and the Biomedical Advanced ...

PEGylation

Macrogols are also attached to biopharmaceutical drugs to slow down their degradation in the human body and increase their duration of action, as well as to reduce

immunogenicity Immunogenicity is the ability of a foreign substance, such as an antigen, to provoke an immune response in the body of a human or other animal. It may be wanted or unwanted: * Wanted immunogenicity typically relates to vaccines, where the injecti ...

. This process is called

PEGylation PEGylation (or pegylation) is the process of both covalent and non-covalent attachment or amalgamation of polyethylene glycol (PEG, in pharmacy called macrogol) polymer chains to molecules and macrostructures, such as a drug, therapeutic protein ...

Contraindications

Contraindications for macrogol taken orally as a laxative are

intestinal perforation Gastrointestinal perforation, also known as gastrointestinal rupture, is a hole in the wall of the gastrointestinal tract. The gastrointestinal tract is composed of hollow digestive organs leading from the mouth to the anus. Symptoms of gastroi ...

bowel obstruction Bowel obstruction, also known as intestinal obstruction, is a mechanical or Ileus, functional obstruction of the Gastrointestinal tract#Lower gastrointestinal tract, intestines which prevents the normal movement of the products of digestion. Ei ...

ileus Ileus is a disruption of the normal propulsive ability of the intestine. It can be caused by lack of peristalsis or by mechanical obstruction. The word 'ileus' derives . The term 'subileus' refers to a partial obstruction. Signs and symptoms S ...

inflammatory bowel disease Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the colon and small intestine, with Crohn's disease and ulcerative colitis (UC) being the principal types. Crohn's disease affects the small intestine and large intestine ...

s, and

toxic megacolon Toxic megacolon is an acute form of colonic distension. It is characterized by a very dilated Colon (anatomy), colon (megacolon), accompanied by abdominal distension (bloating), and sometimes fever, abdominal pain, or Shock (circulatory), shock. ...

. The doses of macrogol as an

are too low to have relevant contraindications.

Allergy Allergies, also known as allergic diseases, are various conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include Allergic rhinitis, hay fever, Food allergy, food al ...

to macrogol is rare, and usually appears as an allergy to an increasing number of seemingly unrelated products, including cosmetics, drugs that use it as an excipient, and peri-procedural substances such as ultrasound gel.

Adverse effects

Oral macrogol is generally well tolerated. Possible side effects include headache, bloating, nausea,

allergies Allergies, also known as allergic diseases, are various conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include Allergic rhinitis, hay fever, Food allergy, food al ...

, and

electrolyte imbalance Electrolyte imbalance, or water-electrolyte imbalance, is an abnormality in the concentration of electrolytes in the body. Electrolytes play a vital role in maintaining homeostasis in the body. They help to regulate heart and neurological function ...

, mainly

hypokalaemia Hypokalemia is a low level of potassium (K+) in the blood serum. Mild low potassium does not typically cause symptoms. Symptoms may include feeling tired, leg cramps, weakness, and constipation. Low potassium also increases the risk of an ...

(low blood

potassium Potassium is a chemical element; it has Symbol (chemistry), symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to ...

levels) and

hyperkalaemia Hyperkalemia is an elevated level of potassium (K+) in the blood. Normal potassium levels are between 3.5 and 5.0mmol/L (3.5 and 5.0 mEq/L) with levels above 5.5mmol/L defined as hyperkalemia. Typically hyperkalemia does not cause symptoms. Occ ...

(high blood potassium levels). Hyperkalaemia is not an effect of macrogol itself but of potassium salts which are usually part of macrogol formulations.

Interactions

The interaction potential is low. Absorption of other pharmaceutical drugs can be reduced because oral macrogol accelerates intestinal passage, but this is seldom clinically relevant. For antiepileptic drugs, such a mechanism has been described in rare cases.

Pharmacology

Mechanism of action as a laxative

Macrogol is an osmotically acting laxative; that is, an inert substance that passes through the gut without being absorbed into the body. It relieves

because it causes water to be retained in the bowel instead of being absorbed into the body. This increases the water content and volume of the stools in the bowel, making them softer and easier to pass, as well as improving

gut motility Peristalsis ( , ) is a type of intestinal motility, characterized by radially symmetrical contraction and relaxation of muscles that propagate in a wave down a tube, in an anterograde direction. Peristalsis is progression of coordinated cont ...

Chemistry

Available forms

When sold for gut cleansing (and as a laxative), it is usually in combination with salts such as

sodium bicarbonate Sodium bicarbonate ( IUPAC name: sodium hydrogencarbonate), commonly known as baking soda or bicarbonate of soda (or simply “bicarb” especially in the UK) is a chemical compound with the formula NaHCO3. It is a salt composed of a sodium cat ...

sodium chloride Sodium chloride , commonly known as Salt#Edible salt, edible salt, is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. It is transparent or translucent, brittle, hygroscopic, and occurs a ...

and

potassium chloride Potassium chloride (KCl, or potassium salt) is a metal halide salt composed of potassium and chlorine. It is odorless and has a white or colorless vitreous crystal appearance. The solid dissolves readily in water, and its solutions have a sa ...

to help mitigate the possibility of electrolyte imbalance and

dehydration In physiology, dehydration is a lack of total body water that disrupts metabolic processes. It occurs when free water loss exceeds intake, often resulting from excessive sweating, health conditions, or inadequate consumption of water. Mild deh ...

. Brand names include Cosmocol, Cololyt, Glycoprep, Laxido, Miralax, Molaxole, Movicol, and Osmolax. Polyethylene glycol-electrolyte solution is a

fixed-dose combination A combination drug is a combination of two or more pharmaceutical drugs as active ingredients combined into a single dosage form, typically as a ''fixed-dose combination'', with each constituent standardized to specifications of a fixed dose. Fix ...

medication sold under various brand names in the US, including Colyte, Gavilyte, Golytely, Nulytely, Moviprep, and Trilyte. Brand names available in the UK include Cosmocol, Klean-Prep, Laxido, Molaxole, Movicol, Plenvu, Transisoft, and Vistaprep. , polyethylene glycol 3350 is available in the US as a combination with sodium sulfate, potassium chloride, magnesium sulfate, and sodium chloride and sold under the brand name Suflave. It is

indicated In medicine, an indication is a valid reason to use a certain test, medication, procedure, or surgery. There can be multiple indications to use a procedure or medication. An indication can commonly be confused with the term diagnosis. A diagnosis ...

for cleansing of the colon in preparation for colonoscopy in adults.

Research

PEGylation

When attached to various biopharmaceutical medications (which are proteins), macrogol results in a slowed clearance of the carried protein from the blood. This makes for a longer-acting medicinal effect and reduces

toxicity Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacteria, bacterium, or plant, as well as the effect o ...

, and it allows for longer dosing intervals. It also reduces the proteins' immunogenicity. Examples for PEGylated proteins include peginterferon alfa-2a and -2b, which are used to treat

hepatitis C Hepatitis C is an infectious disease caused by the hepatitis C virus (HCV) that primarily affects the liver; it is a type of viral hepatitis. During the initial infection period, people often have mild or no symptoms. Early symptoms can include ...

, pegfilgrastim, which is used to treat

neutropenia Neutropenia is an abnormally low concentration of neutrophils (a type of white blood cell) in the blood. Neutrophils make up the majority of circulating white blood cells and serve as the primary defense against infections by destroying bacteria ...

, and pegloticase for the treatment of

gout Gout ( ) is a form of inflammatory arthritis characterized by recurrent attacks of pain in a red, tender, hot, and Joint effusion, swollen joint, caused by the deposition of needle-like crystals of uric acid known as monosodium urate crysta ...

Nerves and spinal cords

There is evidence demonstrating PEG-induced repair of specific nerve cells in animal models: * It has been shown that macrogol can improve healing of spinal injuries in dogs. * One of the earlier findings is that macrogol can aid in nerve repair in

earthworms An earthworm is a soil-dwelling terrestrial animal, terrestrial invertebrate that belongs to the phylum Annelida. The term is the common name for the largest members of the class (biology), class (or subclass (biology), subclass, depending on ...

. * The subcutaneous injection of macrogol 2000 in guinea pigs after spinal cord injury leads to rapid recovery through molecular repair of nerve membranes. The effectiveness of this treatment to prevent

paraplegia Paraplegia, or paraparesis, is an impairment in motor or sensory function of the lower extremities. The word comes from Ionic Greek () "half-stricken". It is usually caused by spinal cord injury or a congenital condition that affects the neura ...

in humans after an accident is not known yet. * Macrogol is being used in the repair of motor neurons damaged in crush or laceration incidents ''

in vivo Studies that are ''in vivo'' (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, an ...

'' and ''

in vitro ''In vitro'' (meaning ''in glass'', or ''in the glass'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in ...

'' in rats. When coupled with melatonin, 75% of damaged sciatic nerves were rendered viable.

Cancer prevention

* High-molecular-weight macrogol (e.g., 8000 g/mol) has been shown to be a dietary preventive agent against

colorectal cancer Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the Colon (anatomy), colon or rectum (parts of the large intestine). Signs and symptoms may include Lower gastrointestinal ...

in animal models. * The Chemoprevention Database shows macrogol is the most effective known agent for the suppression of chemical carcinogenesis in rats. Cancer prevention applications in humans, however, have not yet been tested in

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human subject research, human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel v ...

Other

* Macrogol is also used to fuse B-cells with

myeloma Multiple myeloma (MM), also known as plasma cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white blood cell that normally produces antibodies. Often, no symptoms are noticed initially. As it progresses, bone pain, a ...

cells in

monoclonal antibody A monoclonal antibody (mAb, more rarely called moAb) is an antibody produced from a cell lineage made by cloning a unique white blood cell. All subsequent antibodies derived this way trace back to a unique parent cell. Monoclonal antibodie ...

production.

References

External links

* * {{Authority control Laxatives Excipients Drugs developed by Merck & Co. Drugs developed by Bayer Combination drugs Wikipedia medicine articles ready to translate