Psyllium products are generally well tolerated for up to 6 weeks if taken as directed and with adequate water intake. The main side effects of psyllium products are related to stomach disturbances, including passing more gas, bloating, stomach pain, nausea, vomiting, and skin rash. If you notice other symptoms while using psyllium, such as bleeding from the rectum, seek immediate medical attention.
Some people using psyllium products have experienced serious allergic reactions, including anaphylaxis resulting in sudden breathing problems. If you experience any difficulty breathing, vomiting, or chest pain, seek immediate medical attention. Do not use psyllium if you are allergic to psyllium, the Plantago lanceolata plant known as English plantains, any other member of the Plantaginaceae plant family.
You should also see your doctor if you:
- have persisting (more than 7 days) or worsening symptoms while taking psyllium
- are taking agents that can slow down intestinal movement (e.g., opioids, loperamide)
- have a disease of the esophagus
- have a blockage of the intestines
- had a recent abdominalabdominalrelating to the stomach and intestines surgery
- have hard stools that cannot be passed
- have inflammation of bowel or appendix
- have symptoms of nausea, vomiting, fever, and stomach pain
Psyllium must be taken with adequate amounts of fluid. Without enough water, psyllium can swell and block the throat or intestines and may cause choking and bowel obstruction.
People who have diabetes should use psyllium products with caution, since psyllium can lower blood sugar. It can also drop your blood pressure, and people with low blood pressure or taking blood pressure medications should use it with care.
Women who are pregnant or breast-feeding should use psyllium only on the advice of a health care professional.
Do not use psyllium if you have:
Psyllium products may interfere with the absorption of other medications and supplements, and so should be taken at least 2 hours before or after other medications. This is especially important for people taking medications such as carbamazepine, digoxin, lithium, ASA (e.g., Aspirin®), clopidogrel, NSAIDs, heparin, and warfarin, where changes in the levels of these medications could result in how well the medication works and controls your symptoms. Psyllium products can also interfere with the absorption of medications that are slowly released from specially designed tablets or capsules. Ask your pharmacist if the medication you are taking may interfere with psyllium.
Before taking any new medications, including natural health products, speak to your physician, pharmacist, or other health care provider. Tell your health care provider about any natural health products you may be taking.