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Metamucil

Generic name: Psyllium 
Dosage form: powder, capsules, gummies, fibre thins
Drug class: Laxatives

Medically reviewed by Melisa Puckey, BPharm. Last updated on July 24, 2025.

What is Metamucil?

Metamucil contains psyllium, a plant-based fiber, that is used to treat constipation and other digestive health issues. Metamucil may also help lower cholesterol levels, reduce appetite, and benefit blood sugar levels.

Metamucil provides fibre in your diet that absorbs water and swells to form an undigestible gel that helps soften the stool and improve constipation.  The gel may also help reduce cholesterol by trapping bile and cholesterol in the gut, so instead of being reabsorbed, it passes out of the body as waste. Metamucil’s bulking effect can increase the feeling of fullness to help control appetite and slow glucose absorption into the blood. 

Metamucil is available as powder, capsules, gummies, and fibre thins.

Before taking this medicine

Do not take Metamucil if you have an allergy to psyllium or any inactive ingredients in this product.

Ask a doctor or pharmacist if it is safe to use this medicine if you have ever had:

Tell your doctor if you are pregnant, plan on getting pregnant, or are breastfeeding. You will need to talk about the benefits and risks to you and the baby.

Important information

How should I take this medicine?

Use Metamucil as directed by your doctor or healthcare professional. Read all information given to you. Follow all instructions closely.

This product can swell in your throat and cause choking if you don't take it with enough liquid. Drink plenty of fluids each day to help improve bowel regularity.

Always take this medicine with a full glass (at least 8 ounces) of cool or cold water or other liquid.

Powder must be mixed with liquid before you take it. Do not swallow the dry powder. Mix with at least 8 ounces of liquid such as water or fruit juice. Stir and drink this mixture right away. Add a little more water to the glass, swirl gently, and drink right away.

Swallow capsules one at a time and stay in an upright position.

Metamucil usually produces a bowel movement within 12 to 72 hours.

Call your doctor if your symptoms do not improve, or if they get worse.

Psyllium may be only part of a complete program of treatment that also includes diet, exercise, and weight control. Follow your doctor's instructions very closely.

Store at room temperature away from moisture and heat. Keep the container tightly closed when not in use.

What do I do if I miss a dose?

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Metamucil side effects

Common Metamucil side effects are bloating, stomach cramps, or a minor change in bowel habits.

Serious side effects

Get emergency medical help if you have signs of an allergic reaction, including hives, difficulty breathing, or swelling of your face, lips, tongue, or throat.

Metamucil may cause other serious side effects. Stop using  this medicine and call your doctor at once if you have:

This is not a complete list of side effects, and others may occur. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

How do I store and discard Metamucil?

What other drugs will affect this medicine?

Metamucil can make it harder for your body to absorb other medicines that you take by mouth, possibly making them less effective. If you take any oral medicines, take them 2 hours before or 2 hours after you take this medicine.

Other drugs may affect this medicine, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Does Metamucil interact with my other drugs?

Enter medications to view a detailed interaction report using our Drug Interaction Checker.

Popular FAQ

Metamucil vs. MiraLAX: How do they compare?

Metamucil and MiraLAX are both brand names for over-the-counter laxatives. This means they help you move feces through your bowels. Metamucil is used to help you have regular bowel movements if you have occasional constipation and you can use it every day. MiraLAX is used to treat occasional constipation. It contains a substance called polyethylene glycol. You should not use it for more than 7 days. Continue reading

Is psyllium an affordable weight loss option to Ozempic?

While psyllium husk products like Metamucil may be more affordable than Ozempic, it may not be an equivalent alternative for weight loss. Head-to-head studies have not been done to compare these products, they have different actions in the body and separate studies have shown greater weight loss with Ozempic. Continue reading

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.