What is Hyoscyamine? Uses, warnings & side effects

Take this medicine as directed.

Take doses on an empty stomach 60 minutes before eating.

Swallow immediate-release hyoscyamine tablets whole with a drink of water.

Swallow extended-release hyoscyamine tablets whole with a drink of water. Do not chew or break the tablet.

Chewable tablets can be chewed or allowed to dissolve on the tongue.

• Chewable tablets can be taken with or without water.

Orally disintegrating tablets can be swallowed or allowed to dissolve on the tongue.

• Some orally disintegrating tablets can be taken sublingually. Ask the prescriber or pharmacist.

• Orally disintegrating tablets can be taken with a drink of water.

Sublingual tablets should be placed under the tongue and kept there until completely dissolved.

• Some sublingual tablets can be swallowed or dissolved on the tongue. Ask the pharmacist or prescriber.

• Sublingual tablets can be taken with water.

Measure the oral solution or elixir with a marked measuring spoon, oral syringe, or medicine cup. If the medicine comes with a dropper, use the dropper to measure each dose.

Store hyoscyamine in a light-resistant closed container at room temperature.

Take a dose as soon as you remember. 

If it is almost time for your next dose, wait until then and take a regular dose. 

Do not take extra medicine to make up for a missed dose.

This medicine is not right for everyone. 

Do not use it if you have:

• Glaucoma

• Urinary obstruction

• Gastrointestinal obstruction

• Intestinal paralysis

• Myasthenia gravis

• Known allergies to hyoscyamine

Some emergency and life-threatening medical conditions are also contraindicated:

• Extreme colon swelling (toxic megacolon)

• Uncontrolled bleeding with unstable cardiovascular status (low blood pressure, insufficient circulation, and rapid heart rate)

Tell any doctor or other healthcare provider who treats you that you are using this medicine.

The doctor may require follow-up visits to monitor your condition. Keep all appointments.

Tell the prescriber if you are pregnant, breastfeeding, or have:

• Glaucoma

• Trouble urinating

• Digestive system problems

• Heart disease

• Heart failure

• Heart rhythm abnormalities

• High blood pressure

• Kidney disease

• Hiatal hernia associated with gastric reflux

Hyoscyamine can cause serious problems, including slowed gastrointestinal passage or psychosis.

This medicine may cause you to sweat less and overheat. Avoid hot temperatures.

This medicine may cause dizziness, drowsiness, or blurred vision. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.

This medicine may reduce salivation, increasing the risk of dental cavities, gum disease, and yeast infections in the mouth.

Some drugs or supplements can affect how hyoscyamine works. Tell the prescriber about all prescription drugs, over-the-counter medications, and supplements being taken, particularly:

• Other anticholinergic drugs

• Drugs that treat muscle weakness

• Narcotic pain medicine

• Diarrhea treatments

• MAO inhibitors (MAOIs)

• Tricyclic antidepressants

• Antihistamines

• Phenothiazine drugs

• Amantadine, cyclopropane, ketoconazole, metoclopramide, potassium chloride, quinidine

If you take an antacid, do not take it at the same time you take hyoscyamine. Take each hyoscyamine dose at least 60 minutes before a meal and at least two hours before taking an antacid.