Hyoscyamine

Hyoscyamine is used to treat various stomach and intestinal issues, such as peptic ulcer and irritable bowel syndrome. It helps control muscle spasms in the bladder, kidneys, or digestive tract, and it reduces stomach acid.

Hyoscyamine is sometimes used to lessen tremors and stiff muscles in people showing symptoms of Parkinson's disease.

Hyoscyamine can also be used as a drying agent to manage excessive salivation, a runny nose, or excessive sweating.

Hyoscyamine may also be used for other reasons not mentioned in this medication guide.

Follow all instructions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Always follow the instructions on the medicine label when giving hyoscyamine to a child.

Swallow an extended-release tablet whole. Do not crush, chew, or break it.

Measure liquid medicine carefully. Use the dosing syringe provided or a medicine dose-measuring device (not a kitchen spoon).

Only remove an orally disintegrating tablet from the package when you are ready to take the medicine. Place the tablet on your tongue and let it dissolve. Swallow several times as the tablet dissolves. You may drink water after the tablet has completely dissolved.

Store at room temperature, away from moisture and heat.

You should not use hyoscyamine if you have problems with urination, a blockage in the stomach or bowels, severe ulcerative colitis, glaucoma, or myasthenia gravis.

You should not use hyoscyamine if you are allergic to it, or if you have:

• a bladder obstruction or other urination problems;
• an enlarged prostate;
• a stomach or bowel obstruction (including paralytic ileus);
• severe ulcerative colitis, or toxic megacolon;
• glaucoma; or
• myasthenia gravis.

Hyoscyamine is not approved for use by anyone younger than 2 years old.

Tell your doctor if you have ever had:

• heart problems;
• high blood pressure;
• kidney disease;
• a colostomy or ileostomy;
• a thyroid disorder; or
• hiatal hernia with GERD (gastroesophageal reflux disease).

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It may not be safe to breast-feed while using this medicine. Ask your doctor about any risk.

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

Hyoscyamine may cause serious side effects. Stop using hyoscyamine and call your doctor immediately if you have:

• anxiety, confusion, hallucinations, unusual thoughts or behavior;
• weakness, memory problems;
• slurred speech;
• problems with balance or muscle movement;
• diarrhea;
• pounding heartbeats or fluttering in your chest.

Common side effects of hyoscyamine may include:

• dizziness, drowsiness, feeling weak or tired;
• decreased sweating, decreased urination;
• blurred vision;
• rash;
• dry mouth, decreased sense of taste;
• stomach pain, nausea, vomiting, bloating;
• diarrhea, constipation;
• headache;
• sleep problems (insomnia); or
• impotence, loss of interest in sex, or trouble having an orgasm.

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 FDA at 1-800-FDA-1088.

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

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

Overdose symptoms may include headache, dizziness, dry mouth, trouble swallowing, nausea, vomiting, blurred vision, hot dry skin, and feeling restless or nervous.

Do not take antacids at the same time as hyoscyamine. Antacids can make it harder for your body to absorb hyoscyamine. If you use an antacid, take it after you have taken hyoscyamine and eaten a meal.

Drinking alcohol with hyoscyamine can cause side effects.

Do not become overheated or dehydrated during exercise and in hot weather. Hyoscyamine can decrease sweating, and you may be more prone to heat stroke.

Do not drive or do hazardous activities until you know how this medicine will affect you. Your reactions could be impaired.

Tell your doctor about all your other medicines, especially:

• an antidepressant;
• medicine to treat mental illness;
• cold or allergy medicine (like Benadryl and others);
• medicine to treat or prevent nausea and vomiting; or
• an MAO inhibitor—such as isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, tranylcypromine, and others.

This list is not complete. Other drugs may affect hyoscyamine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.