Levsin (Hyoscyamine)

This Drug May Be Given To Relax Smooth Muscle Tissue

close-up of pills of various sizes

ShutterWorx / E+ / Getty Images

Levsin is classified as an anticholinergic-sedative and is a combination of two drugs: belladonna alkaloids and barbiturates. With the generic name of Hyoscyamine and a brand name of Anaspaz, Levisin is a medication prescribed by a physician in order to relax the muscles in the bladder and intestines as well as reduce stomach acid. It can cause a decrease in saliva production and sweating. Levsin may also be used to treat irritable bowel syndrome (IBS), diverticulosis, and/or bladder spasms.

How Levsin is Taken

Levsin should be taken anywhere from 30 to 60 minutes before eating a meal. It should never be taken at the same time as antacids (such as Tums or Rolaids) because these medications can decrease the absorption of Levsin by the body. Wait at least an hour after taking Levsin to take antacids.

What to do About Missing a Dose

If you miss a dose, take it as soon as you remember. If your next dose should be taken soon, just take that dose. Don't double up, or take more than one dose at a time.

Those Who Should Not Take Levsin

Before taking Levsin, tell your doctor if you have, or have ever had:

  • Asthma, emphysema, or chronic lung disease
  • Congestive heart failure
  • Down's syndrome
  • Glaucoma
  • Hypertension (high blood pressure)
  • Intestinal blockage
  • Kidney disease
  • Liver disease
  • Myasthenia gravis
  • Prostate enlargement (BPH)
  • Severe ulcerative colitis where bowel movements have stopped

Levsin Side Effects

The most serious potential Levsin side effects are confusion, blurred vision, difficulty in urination, and decreased sweating. If these symptoms occur after taking Levin, contact a doctor immediately. It is important to drink enough water while taking this drug, particularly in hot weather or while exercising. People who have dry eye or who wear contact lenses may need to increase the use of rewetting drops. Other common Levsin side effects include headache, nausea, constipation, rash, and vomiting.

Medication Interactions

Levsin can interact with several different classes of drugs. For this reason, it is important for a physician prescribing this medication to know about all other drugs and supplements (even vitamins) that are being taken. This is especially true when taking any of the medications from the following list, because they may interact with the Levsin:

  • Antacids
  • Anticoagulants
  • Antidepressants
  • Antihistamines
  • Amantadine
  • Cardiac rhythm regulators
  • Cimetidine
  • Digoxin
  • Metoclopramide
  • Monoamine oxidase (MAO) inhibitors
  • Potassium chloride
  • Prednisone
  • Sedatives
  • Thiazide diuretics

Food Interactions

Consuming alcohol while taking Levsin could have a sedative effect and cause increased tiredness or sleepiness. People taking Levsin shouldn't drink alcohol for this reason. Take care to avoid alcohol from unexpected sources, such as over-the-counter cough suppressants or cold products (Nyquil, for example). Levsin may also cause constipation in some people. Eating a high fiber diet and drinking plenty of water should help to avoid the development of constipation.

Safety During Pregnancy

The FDA has classified Levsin as a type C drug. The belladonna portion of Levsin has not been shown to cause any problems for pregnant women. However, the barbiturate portion does increase the risk of birth defects and bleeding in newborns.

Levsin does pass into breast milk and therefore could be taken up by a nursing infant. It's speculated that a single dose of Levsin in a breastfeeding mother might not be a cause for great concern, but it is known that infants are particularly sensitive to this type of drug. It's not known how Levsin may affect a nursing infant.

Levsin should only be used during pregnancy if clearly needed. Notify the prescribing doctor if you become pregnant while taking Levsin. The potential for serious side effects in an infant should be weighed against the usefulness of the medication to the mother.

Sexual Side Effects

Levsin is associated with impotence (erectile dysfunction) in men. Levsin may also suppress the production of breast milk in nursing mothers.

A Word From Verywell

Levsin is one of many medications that are used to treat IBS. It may be helpful for some people with IBS, but there are precautions that should be used while taking it. Alcohol needs to be avoided while taken Levsin to avoid becoming very drowsy.

Levsin should probably be avoided by pregnant women or breastfeeding mothers, but this is best discussed with physicians such as an obstetrician/gynecologist and pediatrician, and healthcare professionals such as a lactation consultant. 

Was this page helpful?

Article Sources