Monobasic sodium phosphate + dibasic sodium phosphate - oral

Patient Medicine Information
Why do I need this medicine?
Monobasic sodium phosphate and Dibasic sodium phosphate are combined in this medicine.

It is used to cleanse the bowel before surgery or bowel examinations.

This medicine belongs to a group of medicines called osmotic laxatives. These laxatives work by increasing water in the bowel which makes the stools softer, so they move out of the body more easily.
How do I take this medicine?
Take Monobasic sodium phosphate + Dibasic sodium phosphate exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.

It is important that you drink only clear liquid before you start taking this medicine up until after your examination. Clear liquids may include water, clear soup, clear soda or pulp-free fruit juice. Avoid purple- or red-coloured liquids. Do not eat any solid food.

This medicine is available as a tablet or oral solution.

If you are taking the tablet, take each dose with a full glass (240 mL) of clear liquid.

If you are taking the oral solution, dilute it in 120 mL of cold water followed by a full glass (240 mL) of water. The amount of water needed for the dilution of this medicine may vary with the product given to you. You may discuss with your doctor on how you should properly take your medicine.

Ensure that you drink enough water or clear liquid to prevent dehydration.
When should I not use this medicine?
Alert your doctor if you have the following conditions:
  • stomach and bowel disease or disorder e.g. blocked bowel, ruptured bowel, inborn or acquired swollen colon, abnormal accumulation of fluid within the spaces of the abdomen, lack of normal bowel movement, inflammation of the bowels
  • high level of parathyroid hormone associated with high calcium levels
  • proven kidney injury due to formation of phosphate crystals
  • heart failure
  • uncontrolled chest pain
  • hypothyroidism (underactive thyroid gland)
  • scleroderma (a rare disease that affects the skin, connective tissues, and internal organs)
  • history of stomach surgery for weight loss
  • kidney disease
as Monobasic sodium phosphate + Dibasic sodium phosphate may not be suitable for you.

Do not take this medicine when you are experiencing nausea, vomiting, and stomach pain.

Do not take Monobasic sodium phosphate + Dibasic sodium phosphate with other constipation medicines or enema products containing sodium phosphate.
What should I take note of while taking this medicine?
Inform your doctor if you have the following conditions:
  • previous electrolyte imbalance (imbalance of essential minerals in the body)
  • other heart disease or problem e.g. recent heart attack, irregular or abnormal heartbeat
  • history of seizures (fits)
  • weakened or damaged gag reflex (protective reflex to prevent an object from entering the throat) or other swallowing difficulties
  • any condition that increases your risk of hypomotility disorder (reduced contraction of the muscles that mix and propel contents in the stomach and intestines)
  • low blood pressure which may be associated with low volume of circulating blood in the body
  • diabetes
Let your doctor know if you are pregnant or breastfeeding.

Be sure to check with your doctor or pharmacist before giving Monobasic sodium phosphate + Dibasic sodium phosphate to an elderly or debilitated patient (a person who is physically or mentally weak usually due to illness or old age). Elderly people or debilitated patients may be more sensitive to the side effects.

Your doctor may perform certain blood tests before you take this medicine and then after a procedure to check your body's response to the medicine. Your doctor will advise you if you need to have these blood tests.
What side effects could I experience?
Monobasic sodium phosphate + Dibasic sodium phosphate may cause dizziness which may be due to dehydration. If affected, do not drive or take part in any activity in which you need to be alert.

Other side effects include any of the following: headache, nausea, vomiting, diarrhoea, stomach pain, bloating, weakness, and chills.

Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
  • rashes, breathlessness, swelling of the face, eyes or mouth
  • very bad dizziness or passing out, extreme thirst, confusion, muscle weakness, spasms or cramps
  • fits or seizures
  • irregular or abnormal heartbeats
  • severe stomach pain or bleeding from the rectum
  • unable to pass urine or change in how much urine is passed, blood in urine, swelling of ankles, feet and legs
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Can I take this with other medicines?
Do not take Monobasic sodium phosphate + Dibasic sodium phosphate with other constipation medicines or enema products containing sodium phosphate.

Inform your doctor and pharmacist if you are taking any of these medicines:
  • medicines for high blood pressure e.g. enalapril, losartan
  • water pills or medicines for water retention
  • medicines to treat depression e.g. amitriptyline, nortriptyline
  • NSAIDs (medicines for pain and inflammation) e.g. ibuprofen
  • lithium (medicine for mood disorders)
This list does not include all medicines that may interact with this medicine.

Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
What special dietary instructions should I follow?
Avoid alcohol.
How should I store this medicine?
Store in a cool, dry place away from the reach of children.

Medicines must not be used past the expiry data.
This information is independently developed by MIMS based on monobasic sodium phosphate + dibasic sodium phosphate - oral and is provided for your reference only. It is not a replacement for and should only be used in conjunction with full consultation with a licensed healthcare professional, the information provided by your pharmacist and/or the manufacturer of the medication. It may not contain all the available information you require and cannot substitute professional medical care, nor does it take into account all individual circumstances. Although great effort has been made to ensure content accuracy, we shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2021 MIMS. All rights reserved. Powered by
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