Pro-Banthine Description

Pro-Banthine®(propantheline bromide) oral tablets contain 15 mg or 7.5 mg of the anticholinergic propantheline bromide, (2-hydroxyethyl) diisopropylmethylammonium bromide xanthene-9-carboxylate.

The structural formula of propantheline bromide is:

Propantheline bromide is very soluble in water, alcohol, and chloroform, but it is practically insoluble in ether and in benzene. Its molecular weight is 448.40.

Inactive Ingredients: include calcium carbonate, castor oil, corn starch, lactose anhydrous, light mineral oil, magnesium carbonate, magnesium stearate, saccharin sodium, sucrose, talc, titanium dioxide, and waxes. The 15-mg tablet also contains cosmetic ochre and cosmetic red as coloring agents.

Pro-Banthine - Clinical Pharmacology

Propantheline bromide inhibits gastrointestinal motility and diminishes gastric acid secretion. The drug also inhibits the action of acetylcholine at the post-ganglionic nerve endings of the parasympathetic nervous system.

Propantheline bromide is extensively metabolized in man primarily by hydrolysis to the inactive compounds xanthene-9-carboxylic acid and (2-hydroxyethyl) diisopropylmethylammonium bromide. After a single 30-mg oral dose given as two 15-mg tablets, the mean peak plasma concentration of propantheline was 21 ng/mL at 1 hour in 6 healthy subjects.

The plasma elimination half-life of propantheline is about 1.6 hours. Approximately 70% of the dose is excreted in the urine, mostly as metabolites. The urinary excretion of propantheline is about 3% after oral tablet administration.

Indications and Usage for Pro-Banthine

Pro-Banthine® (propantheline bromide) tablets are as effective as adjunctive therapy in the treatment of peptic ulcer.

Contraindications

Propantheline bromide is contraindicated in patients with:

1. Glaucoma, since mydriasis is to be avoided.
2. Obstructive disease of the gastrointestinal tract (pyloroduodenal stenosis, achalasia, paralytic ileus, etc.)
3. Obstructive uropathy (e.g., bladder-neck obstruction due to prostatic hypertrophy).
4. Intestinal atony of elderly or debilitated patients.
5. Severe ulcerative colitis or toxic megacolon complicating ulcerative colitis.
6. Unstable cardiovascular adjustment in acute hemorrhage.
7. Myasthenia gravis.

Warnings

In the presence of a high environmental temperature, heat prostration (fever and heat stroke due to decreased sweating) can occur with the use of Pro-Banthine®.

Diarrhea may be an early symptom of incomplete intestinal obstruction, especially in patients with ileostomy or colostomy. In this instance treatment with propantheline bromide would be inappropriate and possibly harmful.

With overdosage, a curare-like action may occur (i.e., neuromuscular blockage leading to muscular weakness and possible paralysis).

Propantheline bromide may cause increased heart rate and, therefore, should be used with caution in patients with heart disease.

Precautions

Adverse Reactions/Side Effects

Varying degrees of drying of salivary secretions may occur as well as decreased sweating. Ophthalmic side effects include blurred vision, mydriasis, cycloplegia and increased ocular tension. Other reported adverse reactions include urinary hesitancy and retention, tachycardia, palpitations, loss of the sense of taste, headache, nervousness, mental confusion, drowsiness, weakness, dizziness, insomnia, nausea, vomiting, constipation, bloated feeling, impotence, suppression of lactation, and allergic reactions or drug idiosyncrasies, including anaphylaxis, urticaria, and other dermal manifestations.

Overdosage

The symptoms of overdosage with propantheline bromide progress from an intensification of the usual side effects to CNS disturbances (from restlessness and excitement to psychotic behavior), circulatory changes (flushing, fall in blood pressure, circulatory failure), respiratory failure, paralysis, and coma.

Measures to be taken are (1) immediate induction of emesis or lavage of the stomach, (2) injection of physostigmine 0.5 to 2 mg intravenously, repeated as necessary up to a total of 5 mg, and (3) monitoring of vital signs and managing as necessary.

Fever may be treated symptomatically (cooling blanket or alcohol sponging). Excitement of a degree which demands attention may be managed with thiopental sodium 2% solution given slowly intravenously, or diazepam, 5 to 10 mg intravenously or 10 mg intramuscularly. In the event of progression of the curare-like effect to paralysis of the respiratory muscles, mechanical respiration should be instituted and maintained until effective respiratory action returns.

The oral LD50 of propantheline bromide is 780 mg/kg in the mouse and 370 mg/kg in the rat.

Pro-Banthine Dosage and Administration

The usual initial adult dosage of Pro-Banthine®tablets is 15 mg taken 30 minutes before each meal (3 times daily), and 30 mg at bedtime (a total of 75 mg daily). Subsequent dosage adjustment should be made according to the patient's individual response and tolerance. The administration of one 7.5-mg tablet 30 minutes before each meal (3 times daily) is convenient for patients with mild manifestations, for geriatric patients, and for those of small stature.

How is Pro-Banthine supplied

Pro-Banthine®15-mg tablets are round, peach-colored, sugar-coated, with RPC imprinted on one side and 074 on the other side. Bottles of 100 (NDC 54092-074-01).

Pro-Banthine® 7.5-mg tablets are round, white, sugar-coated, with RPC imprinted on one side and 073 on the other side. Bottles of 100 (NDC 54092-073-01).

Store below 25°C (77°F).

Rev. 2/00 073 0117 004