Hello, Boris. I found this on the University of Maryland Medical Center. Read below. Throughout the day, drink lots of water to give the pysillium enough water to keep it moving out. If you drink too little it might swell too much. See below:
Available Forms
Standard preparations of psyllium are available in dry seed or husk form, to be mixed with water as needed. Psyllium is an ingredient ign some commercially-prepared laxatives. It also comes in capsules, tablets, and wafers.
How to Take It
Pediatric
Children should get fiber from their diet. Give a child psyllium supplements only under a doctor's supervision.
Adult
If you use a commercial product that contains psyllium, follow the package directions.
If you are not used to taking psyllium, it is best to begin with a low dose (such as 1/2 tsp. in an 8 oz. glass of water once a day), then gradually increase the dose as needed.
Your health care provider may recommend higher doses of psyllium to treat certain conditions. You can take psyllium first thing in the morning or before bedtime.
Precautions
Because supplements may have side effects or interact with medications, you should take them only under the supervision of a knowledgeable health care provider.
Psyllium supplements may reduce or delay the absorption of certain medications (See Possible Interactions). As a rule, you should not take psyllium supplements at the same time as other medications. Take psyllium at least 1 hour before or 2 to 4 hours after taking other medications.
You should always take psyllium with a full 8 oz. glass of water, and you should drink at least 6 to 8 full glasses of water throughout the day to avoid constipation. Taking psyllium supplements without adequate liquids may cause it to swell, and, in extreme cases, cause choking.
DO NOT take this product if you have bowel obstructions or spasms, or if you have difficulty swallowing. People with esophageal stricture (narrowing of the esophagus) or any other narrowing or obstruction of the gastrointestinal tract should not take psyllium.
A potential side effect from any fiber product is gas and bloating.
People with kidney disease should talk to their doctor before taking psyllium.
Possible Interactions
If you are being treated with any of the following medications, you should not use psyllium supplements without first talking to your health care provider.
Antidepressant medications, Tricyclics
Dietary fiber has been shown to lower the blood levels and effectiveness of tricyclic antidepressant medications in some people. If you take tricyclic antidepressants, talk to your doctor before taking psyllium. Tricyclic antidepressants include:
Amitriptyline (Elavil)
Doxepin (Sinequan)
Imipramine (Tofranil)
Carbemazepine (Tegretol)
Taking psyllium with carbamazepine, a medication used to treat seizures, may decrease the absorption and effectiveness of carbamazepine.
Cholesterol-lowering medications (bile acid sequestrants)
Taking psyllium with cholesterol-lowering medications called bile acid sequestrants may help further lower cholesterol levels and may reduce side effects of colestipol. Talk to your doctor about whether this may be an option for you. Bile acid sequestrants include:
Cholestyramine (Questram)
Colestipol (Colestid)
Diabetes medications
Fiber supplements may reduce levels of blood sugar, making the possibility of hypoglycemia (low blood sugar) more likely. Talk to your doctor before taking fiber supplements, as your dose of diabetes medications may need to be adjusted.