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Drugs & Medications

Hyoscamine

GENERIC NAME(S): PHENOBARBITAL/HYOSCYAMINE SULF/ATROPINE SULF/SCOPOLAMINE HB

Uses

This product contains several medications: belladonna alkaloids (made up of the drugs hyoscyamine, atropine, and scopolamine) and phenobarbital. Belladonna alkaloids help to reduce the symptoms of stomach and intestinal cramping. They work by slowing the natural movements of the gut and by relaxing the muscles in the stomach and intestines. Belladonna alkaloids belong to a class of drugs known as anticholinergics/antispasmodics. Phenobarbital helps to reduce anxiety. It acts on the brain to produce a calming effect. Phenobarbital belongs to a class of drugs known as barbiturate sedatives.

OTHER USES: This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.

This drug may also be used to relieve the symptoms of irritable bowel syndrome.

How to use Hyoscamine

Take this medication by mouth as directed by your doctor. If you are taking the immediate-release tablets or liquid form of this medication, take it usually 3 to 4 times a day or as directed by your doctor.

If you are using the liquid, carefully measure the dose using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose.

If you are taking the extended-release tablets, take them usually every 12 hours or as directed by your doctor. Do not crush or chew extended-release tablets. Doing so can release all of the drug at once, increasing the risk of side effects. Also, do not split the tablets unless they have a score line and your doctor or pharmacist tells you to do so. Swallow the whole or split tablet without crushing or chewing.

Antacids lower the absorption of this medication. If you are taking an antacid, take it at least 2 hours apart from this medication.

The dosage is based on your medical condition and response to treatment. In children, the dosage is also based on weight.

Do not increase your dose or take this drug more often without your doctor's approval. Your condition will not improve any faster and the risk of serious side effects may increase.

This medication may cause withdrawal reactions, especially if it has been used regularly for a long time or in high doses. In such cases, withdrawal symptoms (such as anxiety, muscle twitching, shakiness, dizziness, worsening weakness, nausea, vomiting) may occur if you suddenly stop using this medication. Withdrawal from the phenobarbital can be severe and include seizures and (rarely) death. To prevent withdrawal reactions, your doctor may reduce your dose gradually. Consult your doctor or pharmacist for more details, and report any withdrawal reactions immediately.

When this medication is used for a long time, it may not work as well. Your doctor may need to increase your dose or change your medication. Talk with your doctor if this medication stops working well.

Along with its benefits, this medication may rarely cause abnormal drug-seeking behavior (addiction). This risk may be increased if you have abused alcohol or drugs in the past. Take this medication exactly as prescribed to lessen the risk of addiction.

Tell your doctor if your condition persists or worsens.

Side Effects

Dizziness, drowsiness, weakness, blurred vision, dry eyes, dry mouth, nausea, constipation, and abdominal bloating may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

To relieve dry mouth, suck (sugarless) hard candy or ice chips, chew (sugarless) gum, drink water, or use a saliva substitute. To relieve dry eyes, consult your pharmacist for artificial tears or other eye lubricants.

To prevent constipation, eat a diet adequate in fiber, drink plenty of water, and exercise. Consult your pharmacist for help in selecting a laxative (such as a stimulant type with stool softener).

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor immediately if any of these unlikely but serious side effects occur: decreased sweating, dry/hot/flushed skin, fast/irregular heartbeat, loss of coordination, slurred speech, fainting, mental/mood changes (such as confusion, agitation, unusual excitement, depression, rare thoughts of suicide), eye pain, vision changes, difficulty urinating, decreased sexual ability, slow/shallow breathing.

Tell your doctor immediately if any of these rare but serious side effects occur: signs of anemia (such as unusual tiredness, pale skin), signs of infection (such as fever, persistent sore throat), easy bruising/bleeding.

A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before taking this medication, tell your doctor or pharmacist if you are allergic to hyoscyamine, atropine, scopolamine, or phenobarbital; or to primidone; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: glaucoma, enlarged prostate, problems with urination due to a blocked urinary tract, other stomach/intestinal problems (such as slow gut, blockage, ulcerative colitis, infection, little/no stomach acid, ileostomy/colostomy patients with diarrhea), overactive thyroid, heart problems (such as coronary artery disease, angina, congestive heart failure, fast/irregular heartbeat, heart problems due to severe bleeding), high blood pressure, heartburn problems (such as acid reflux, hiatal hernia, esophagus problems), certain nervous system problem (autonomic neuropathy), myasthenia gravis, liver problems, kidney problems, a certain blood disorder (porphyria), restlessness or excitement during past use of phenobarbital, breathing/lung problems, drug/alcohol abuse, mental/mood conditions (such as depression, thoughts of suicide, psychosis).

This drug may make you dizzy or drowsy or cause blurred vision. Do not drive, use machinery, or do any activity that requires alertness or clear vision until you are sure you can perform such activities safely. Avoid alcoholic beverages.

The liquid form of this product may contain alcohol or sugar. Caution is advised if you have diabetes, alcohol dependence, liver disease, or any other condition that requires you to limit/avoid these substances in your diet. Ask your doctor or pharmacist about using this product safely.

This medication may make you sweat less which can increase your risk for heat stroke, a very serious condition. Avoid activities that might cause you to overheat (such as doing strenuous work/exercise in hot weather, using hot tubs). Drink plenty of fluids, and dress lightly while in hot weather or when exercising. If you become overheated, stop exercising and promptly seek cooler shelter. Seek immediate medical attention if you develop a fever, mental/mood changes, headache, or dizziness.

Older adults may be more sensitive to the side effects of this drug, especially drowsiness, confusion, unusual excitement, constipation, and urination problems. Drowsiness and confusion can increase the risk of falling.

Children may be more sensitive to the side effects of this drug. This drug can often cause excitement instead of drowsiness in young children.

This medication is not recommended for use during pregnancy. It may harm an unborn baby. Consult your doctor for details. Hormonal birth control products (such as pills, patch, ring) may not be effective if taken with this medication (see also Drug Interactions section). Discuss reliable forms of birth control with your doctor.

This medication passes into breast milk and may have undesirable effects on a nursing infant. Consult your doctor before breast-feeding.

Interactions

See also the How to Use section.

The effects of some drugs can change if you take other drugs or herbal products at the same time. This can increase your risk for serious side effects or may cause your medications not to work correctly. These drug interactions are possible, but do not always occur. Your doctor or pharmacist can often prevent or manage interactions by changing how you use your medications or by close monitoring.

To help your doctor and pharmacist give you the best care, be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products) before starting treatment with this product. While using this product, do not start, stop, or change the dosage of any other medicines you are using without your doctor's approval.

Some products that may interact with this drug include: etravirine, potassium tablets/capsules, rilpivirine, sodium oxybate, drugs that are affected by slowed gut movement (such as metoclopramide, pramlintide).

This medication may affect the absorption of other products such as levodopa, griseofulvin, certain azole anti-fungal drugs (ketoconazole, itraconazole), slowly dissolving forms of digoxin, among others.

Many other drugs that also cause dry mouth and constipation may interact with anticholinergics/antispasmodics such as belladonna alkaloids. Tell your doctor or pharmacist about all the products you take, including: amantadine, other anticholinergic drugs (such as atropine, glycopyrrolate, scopolamine), other antispasmodic drugs (such as clidinium, dicyclomine, hyoscyamine, propantheline), certain drugs used to treat Parkinson's disease (such as benztropine, trihexyphenidyl), certain drugs used to treat irregular heart rhythms (such as disopyramide, quinidine), MAO inhibitors (isocarboxazid, linezolid, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, selegiline, tranylcypromine), phenothiazines (such as chlorpromazine), tricyclic antidepressants (such as amitriptyline).

Other medications can affect the removal of phenobarbital from your body, which may affect how this product works. Examples include disulfiram, drugs to treat seizures (such as phenytoin, valproic acid), St. John's wort, among others.

Phenobarbital can speed up the removal of many other medications from your body, which may affect how they work. Examples of affected drugs include cyclosporine, doxycycline, estrogens, metronidazole, ranolazine, voriconazole, "blood thinners" such as warfarin, corticosteroids such as prednisone, calcium channel blockers such as felodipine/nimodipine, among others.

This medication may decrease the effectiveness of hormonal birth control such as pills, patch, or ring. This could cause pregnancy. Discuss with your doctor or pharmacist if you should use additional reliable birth control methods while using this medication. Also tell your doctor if you have any new spotting or breakthrough bleeding, because these may be signs that your birth control is not working well.

Tell your doctor or pharmacist if you are taking other products that cause drowsiness or slow/shallow breathing including alcohol, antihistamines (such as cetirizine, diphenhydramine), drugs for sleep or anxiety (such as alprazolam, diazepam, zolpidem), muscle relaxants, and narcotic pain relievers (such as codeine).

Check the labels on all your medicines (such as allergy or cough-and-cold products, diet aids) because they may contain ingredients that cause drowsiness or a fast heartbeat. Ask your pharmacist about using those products safely.

This medication may interfere with certain laboratory tests (including gastric secretion tests), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.

Phenobarbital is very similar to primidone. Do not use medications containing primidone while using phenobarbital.

This document does not contain all possible drug interactions. Keep a list of all the products you use. Share this list with your doctor and pharmacist to lessen your risk for serious medication problems.

Overdose

If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: large pupils, hot/dry skin, fever, severe dizziness, severe drowsiness, severe thirst, mental/mood changes (such as confusion, unusual excitement), fast/irregular heartbeat, muscle weakness, inability to move (paralysis), slowed breathing, fainting, inability to wake up, seizures.

Notes

Do not share this medication with others.

Management of digestive disorders may include lifestyle changes such as stress reduction programs, exercise, stopping smoking, and dietary changes, in addition to medication. Talk to your doctor or pharmacist about lifestyle changes that might benefit you.

If this medication is used for an extended period of time, laboratory and/or medical tests (such as blood counts, liver function tests) may be performed periodically to check for side effects. Consult your doctor for more details.

Missed Dose

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

Storage

Store at room temperature between 68-77 degrees F (20-25 degrees C) away from light and moisture. Avoid freezing the liquid. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

Information last revised April 2014. Copyright(c) 2014 First Databank, Inc.

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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

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