methylcellulose (OTC)

Brand and Other Names:Citrucel

Dosing & Uses


Dosage Forms & Strengths


  • 500mg


  • 2g/scoop


2 caplets up to 6 times/day; not to exceed 12 caplets/day; follow each dose with 8 oz of water

Alternatively, 1 heaping tablespoon (2 g) in 8 oz water qDay to q8hr

Dosage Forms & Strengths


  • 500mg


  • 2g/scoop

Constipation (6-11 Years Old)

<6 years

  • Safety & efficacy not established

6-12 years old

  • 1 caplet up to 6 times/day; not to exceed 6 caplets/day
  • 1 g (½ tablespoon) in 8 oz of cold water; may increase to 1 tablespoon q8hr

>12 years

  • 2 caplets up to 6 times/day; not to exceed 12 caplets/day; follow each dose with 8 oz of water
  • Alternatively, 1 heaping tablespoon (2 g) in 8 oz water qDay to q8hr


Interaction Checker

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                  Minor (1)

                  • sodium picosulfate

                    methylcellulose decreases effects of sodium picosulfate by Mechanism: unspecified interaction mechanism. Minor/Significance Unknown.


                  Adverse Effects

                  Frequency Not Defined



                  Excessive bowel activity




                  Hypersensitivity, bowel obstruction, symptoms of appendicitis or acute surgical abdomen, GI ulceration/adhesions, fecal impaction, dysphagia, rectal bleeding


                  Without taking adequate fluid the product may swell and block your throat or esophagus and may cause choking

                  Do not take this product if difficulty swallowing; if experiencing chest pain, vomiting, or difficulty in swallowing or breathing after taking this product, seek immediate medical attention

                  If rectal bleeding occurs or failure to have a bowel movement after use could be signs of a serious condition

                  Keep out of reach of children; in case of overdose, get medical help or contact a Poison Control Center right away

                  If experiencing abdominal pain, nausea or vomiting or a sudden change in bowel habits that persists over a period of 2 weeks ask a healthcare professional before use

                  Laxatives are not to be used for a period longer than one week unless directed by a doctor

                  Not for use by patients that are on a low-salt diet unless directed by a doctor


                  Pregnancy & Lactation


                  N/A (supplement; not a drug)


                  No data available; not absorbed, unlikely to pose risk in breastfeeding

                  Pregnancy Categories

                  A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

                  B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

                  C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

                  D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

                  X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

                  NA: Information not available.



                  Mechanism of Action

                  Bulk producing laxative


                  Metabolism: Not absorbed from GI tract



                  Pricing & Images are not currently available for this monograph.

                  Patient Handout

                  Patient Education
                  methylcellulose (laxative) oral


                  USES: This medication is used to treat constipation. It increases the bulk in your stool, an effect that helps to cause movement of the intestines. It also works by increasing the amount of water in the stool, making the stool softer and easier to pass.Psyllium, one type of bulk-forming laxative, has also been used along with a proper diet to treat high cholesterol.

                  HOW TO USE: Take this medication by mouth as directed by your doctor. If you are self-treating, follow all directions on the product package. If you have any questions, ask your doctor or pharmacist. To prevent choking from this medication, take it with a full glass of water or other liquid (8 ounces/240 milliliters). If you are taking the wafers, chew them thoroughly before swallowing.For powder forms of this medication, measure each dose according to the directions on the product label. Mix in a full glass of water or other liquid (8 ounces/240 milliliters), stir completely, and drink right away. You may add more liquid to the mixture if it becomes too thick. When preparing the medication, be careful not to breathe in the powder since it may rarely cause an allergic reaction.Dosage is based on your age, medical condition, and response to treatment. Do not increase your dose or take this drug more often than directed.This product may decrease the absorption of other medications you may be taking. Take this product at least 2 hours from your other medications. Ask your doctor or pharmacist for more information or if you have any questions.It may take 1 to 3 days before this medication starts working. Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time(s) each day. Do not take this medication for more than 7 days unless directed by your doctor.Tell your doctor if your condition lasts or gets worse, or if bleeding from the rectum occurs. If you think you may have a serious medical problem, get medical help right away.

                  SIDE EFFECTS: Gas or stomach cramping may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.If your doctor has directed you to use this product, remember that your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.This product must be taken with at least a full glass of water or other liquid (8 ounces/240 milliliters) so that it will not swell in the throat, causing choking. Get medical help right away if after taking this product you have symptoms of choking such as: chest pain, vomiting, difficulty swallowing/breathing.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

                  PRECAUTIONS: Before taking this bulk-forming laxative, tell your doctor or pharmacist if you are allergic it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: stomach/intestinal blockage, difficulty swallowing, appendicitis or symptoms of appendicitis (such as nausea/vomiting, sudden or unexplained stomach/abdominal pain), a sudden change in bowel habits that lasts for longer than 2 weeks, bleeding from the rectum.Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).Some products may contain sugar and/or aspartame. Caution is advised if you have diabetes, phenylketonuria (PKU), or any other condition that requires you to limit/avoid these substances in your diet. Ask your doctor or pharmacist about using this product safely.Tell your doctor if you are pregnant before using this medication.It is unknown if this medication passes into breast milk. Consult your doctor before breast-feeding.

                  DRUG INTERACTIONS: See also How To Use section.Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

                  OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.

                  NOTES: Keep all medical and lab appointments.Lifestyle changes that may prevent or relieve constipation include exercising, drinking enough water, and eating a proper diet with fiber-rich foods such as bran, fresh fruits/vegetables. Talk to your doctor or pharmacist about lifestyle changes that might benefit you.

                  MISSED DOSE: If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

                  STORAGE: Different brands of this medication have different storage needs. Check the product package for instructions on how to store your brand, or ask your pharmacist. Keep all medications away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

                  Information last revised January 2023. Copyright(c) 2023 First Databank, Inc.

                  IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

                  Medscape prescription drug monographs are based on FDA-approved labeling information, unless otherwise noted, combined with additional data derived from primary medical literature.