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hyoscyamine (No Brand Name)

Brand Names: No Brand Name

Generic Name: hyoscyamine

What is hyoscyamine?

Hyoscyamine produces many effects in the body, including relief from muscle spasms.

Hyoscyamine also reduces the fluid secretions of many organs and glands in the body, such as the stomach, pancreas, lungs, saliva glands, sweat glands, and nasal passages.

Hyoscyamine is used to treat many different stomach and intestinal disorders, including peptic ulcer and irritable bowel syndrome. It is also used to control muscle spasms in the bladder, kidneys, or digestive tract, and to reduce stomach acid. Hyoscyamine is sometimes used to reduce tremors and rigid muscles in people with symptoms of Parkinson's disease.

Hyoscyamine is also used as a drying agent to control excessive salivation, runny nose, or excessive sweating.

Hyoscyamine may also be used for purposes not listed in this medication guide.

What are the possible side effects of hyoscyamine?

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

Stop using hyoscyamine and call your doctor at once if you have any of these serious side effects:

  • diarrhea;
  • confusion, hallucinations;
  • unusual thoughts or behavior;
  • fast, pounding, or uneven heart rate;
  • rash or flushing (warmth, redness, or tingly feeling); or
  • eye pain.

Less serious side effects may include:

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.

What is the most important information I should know about hyoscyamine?

Do not take hyoscyamine if you are allergic to it, or if you have kidney disease, a bladder or intestinal obstruction, severe ulcerative colitis, toxic megacolon, glaucoma, or myasthenia gravis.

Before taking hyoscyamine, tell your doctor if you have heart disease, congestive heart failure, a heart rhythm disorder, high blood pressure, overactive thyroid, or hiatal hernia with gastroesophageal reflux disease.

Avoid taking antacids at the same time you take 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.

Hyoscyamine may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Drinking alcohol can increase drowsiness and dizziness while you are taking hyoscyamine.

Avoid becoming overheated or dehydrated during exercise and in hot weather. Hyoscyamine can decrease sweating and you may be more prone to heat stroke.

What should I discuss with my healthcare provider before taking hyoscyamine?

Do not take hyoscyamine if you are allergic to it, or if you have:

To make sure you can safely take hyoscyamine, tell your doctor if you have any of these other conditions:

FDA pregnancy category C. It is not known whether hyoscyamine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.

Hyoscyamine can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take hyoscyamine?

Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Your medication may come with patient instructions for safe and effective use. Follow these directions carefully. Ask your doctor or pharmacist if you have any questions.

Hyoscyamine is usually taken before a meal. Follow your doctor's instructions.

Do not crush, chew, or open an extended-release tablet or capsule. It is specially made to release medicine slowly in the body. Breaking or crushing the pill would cause too much of the drug to be released at one time. Your doctor may want you to break an extended-release tablet and take only half of it. Follow your doctor's instructions.

Measure the oral liquid form of hyoscyamine with a special dose-measuring spoon or cup, not a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

The sublingual tablet form of this medication must be placed under the tongue, where it will dissolve. Do not swallow the sublingual tablet whole or wash it down with water. You may drink water after the pill has completely dissolved in your mouth.

Before using hyoscyamine oral spray for the first time, you must prime the spray pump. To do this, spray 3 test sprays into the air and away from your face. Prime the spray pump at least 1 test spray any time you have not used the oral spray for longer than 2 days. Spray until a fine mist appears.

After using the oral spray, try not to swallow right away. Do not rinse your mouth or spit for 5 to 10 minutes after using the oral spray.

Store this medication at room temperature away from moisture and heat.

Do not use hyoscyamine oral spray for more than 30 sprays, even if there is medicine still left in the bottle.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention 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.

What should I avoid while taking hyoscyamine?

Avoid taking antacids at the same time you take 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.

Hyoscyamine may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Drinking alcohol can increase drowsiness and dizziness while you are taking hyoscyamine.

Avoid becoming overheated or dehydrated during exercise and in hot weather. Hyoscyamine can decrease sweating and you may be more prone to heat stroke.

What other drugs will affect hyoscyamine?

Tell your doctor about all other medicines you use, especially:

This list is not complete and other drugs may interact with hyoscyamine. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

Where can I get more information?

Your pharmacist can provide more information about hyoscyamine.


Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

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