Frequently Asked Questions about Symax Duotab
  Symax® Duotab 
Frequently Asked Questions
Symax Duotab
Symax® Duotab Package Insert
Product Indications and Usage
Product Warnings
All Products
Symax® Duotab
12 Hour Tablet
Bi Phasic Now and Later Delivery

NDC# 64543-118-90
Immediate release:
0.125 mg Hyoscyamine Sulfate
Sustained release:
0.250 mg Hyoscyamine Sulfate
Rx Only
U.S. Pat. Pending No. 10/879,506

Immediate release you need
Extended release you want

• How does hyoscyamine work?

Hyoscyamine inhibits the actions of acetylcholine on structures innervated by postganglionic nerves and on smooth muscles that respond to acetylcholine but lack cholinergic innervation.

• What is the difference between Symax DuoTab and a sustained release/generic?

Symax DuoTab is a first of its kind, unique, biphasic tablet that incorporates both an immediate release component for ‘right now’ relief and a sustained release component for prolonged relief. Symax DuoTab eliminates the peaks and valleys of drug availability inherent to traditional delivery and that results in breakthrough symptoms.

• How fast does Symax DuoTab work?

Symax DuoTab’s immediate release component is immediately available and reaches peak serum concentration in about 15-20 minutes while the sustained release component reaches peak serum concentration in about 2 hours.

• Can I use Symax DuoTab on my cardiac patients, especially my hypertensives?

Many physicians prescribe Symax DuoTab for patients that are hypertensive or have an unstable cardiovascular status, including arrhythmias and congestive heart failure. As with any patient with heart problems, your discretion and careful monitoring is advised before giving any anticholinergic drug since they may increase the heart rate and blood pressure.

• Can I use Symax DuoTab on my older geriatric patients?

Geriatric patents frequently respond differently to many medications. Your discretion and careful monitoring of these patients is advised. Occasionally, geriatric patients may respond to normal doses of anticholinergics with excitement, drowsiness, or confusion, since these drug blocks the actions of acetylcholine.

• Can I use Symax DuoTab on my older geriatric patients that are taking several other medications?

It frequently is, however, absorption of other oral medications may be decreased during concurrent use with anticholinergics due to decreased gastrointestinal motility and delayed gastric emptying. Drug interactions may occur when anticholinergics are used with antacids, antidiarrheals, antimyasthenics, cyclopropane, haloperidol, ketoconazole, opioid analgesics, and potassium chloride.

• Should I use Symax DuoTab on patients with myasthenia gravis?

Symax DuoTab is contraindicated for patients with myasthenia gravis. Myasthenia gravis is thought to be associated with impaired ability of the neurotransmitter acetylcholine to induce muscular contractions, therefore you wouldn’t want to administer a drug that inhibits acetylcholine’s actions.

• Should I use Symax DuoTab on patients with obstructive uropathy or obstructive disease of the GI tract?

Symax DuoTab inhibits propulsive motility, therefore, it should not be prescribed for patients with any obstruction of the urinary tract or the GI tract until the nature of the obstruction is ascertained.

• Can Symax DuoTab be prescribed with MAO inhibitors?

Symax DuoTab should be used with caution if patients are taking MAO inhibitors such as Nardil and Parnate. Anytime you have cholinergic blockage additive adverse effects may result.

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