IMPORTANT NOTE: The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate or effective for you. Consult your healthcare professional before using this drug.
Table of Contents
- Uses and How to Use
- Precautions and Side Effects
- Medication Interactions
- Dosage and Storage
- Medication Images
Pronounced:
Symax Fastabs Oral Precautions
Before taking hyoscyamine, tell your doctor or pharmacist if you are allergic to it; 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.
This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have:
- glaucoma (narrow-angle type, untreated open-angle type)
- enlarged prostate
- urinary blockage problems
- certain stomach/intestinal problems (e.g., slow gut, blockage, severe ulcerative colitis, infection)
- heart problems due to severe bleeding
Before using this medication, tell your doctor or pharmacist your medical history, especially of:
- overactive thyroid
- other heart problems (e.g., coronary heart disease, congestive heart failure, fast heartbeat, arrhythmias)
- high blood pressure
- kidney disease
- heartburn problems (acid reflux, hiatal hernia)
- certain nervous system problem (autonomic neuropathy)
- myasthenia gravis
Contact lens wearers may need to use wetting eye drops since this medication can cause dry eyes.
This medicine may contain aspartame. If you have phenylketonuria (PKU) or any other condition where you must restrict your intake of aspartame (or phenylalanine), consult your doctor or pharmacist regarding the safe use of this medicine.
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. Limit alcoholic beverages.
This drug may increase the risk for heatstroke because it decreases sweating. Avoid becoming overheated in hot weather, saunas, and during exercise or other strenuous activity.
Kidney function declines as you grow older. This medication is removed by the kidneys. Therefore, elderly people may be at greater risk for confusion and unusual excitement while using this drug.
Children may be more sensitive to the effects of this drug.
Hyoscyamine should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.
This drug passes into breast milk. Consult your doctor before breast-feeding.
Symax Fastabs Oral Side Effects
Dizziness, drowsiness, blurred vision, dry mouth, vision problems, headache, trouble sleeping, constipation, flushing, dry skin, and decreased sweating may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.
To relieve dry mouth, suck on (sugarless) hard candy or ice chips, chew (sugarless) gum, drink water or use a saliva substitute.
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:
- mental/mood changes (e.g., confusion, unusual excitement)
- fast/irregular heartbeat
- difficulty urinating
- decreased sexual ability
- loss of coordination
- slurred speech
- eye pain
- vomiting
A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include:
- 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.
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.
Information last revised September
2011.
Copyright(c) 2011 First Databank, Inc.

