Cantil (Mepenzolate bromide) tablets for oral administration contain 25 mg mepenzolate bromide USP. The anticholinergic agent mepenzolate bromide USP chemically is 3-[(hydroxydiphenylacetyl)oxy]-1,1-dimethylpiperidinium bromide and has the following structure:

Mepenzolate bromide occurs as a white or light cream-colored powder, which is freely soluble in methanol, slightly soluble in water and chloroform, and practically insoluble in ether.

Each yellow tablet contains 25 mg mepenzolate bromide USP. This tablet also contains inactive ingredients: confectioners' sugar, corn starch, corn syrup solids, FD&C Yellow No. 5 (tartrazine), (see ), lactose, magnesium stearate and microcrystalline cellulose.

Cantil (Mepenzolate bromide) diminishes gastric acid and pepsin secretion. Cantil (Mepenzolate bromide) also suppresses spontaneous contractions of the colon. Pharmacologically, it is a post-ganglionic parasympathetic inhibitor.

Radiotracer studies in which Cantil (Mepenzolate bromide) -C was used in animals and humans indicate the absorption following oral administration, as with other quaternary ammonium compounds, is low. Between 3 and 22% of an orally administered dose is excreted in the urine over a 5-day period, with the majority of the radioactivity appearing on Day 1. The remainder appears in the next 5 days in the feces and presumably has not been absorbed.

Cantil (Mepenzolate bromide) is indicated for use as adjunctive therapy in the treatment of peptic ulcer. It has not been shown to be effective in contributing to the healing of peptic ulcer, decreasing the rate of recurrence, or preventing complications.

In the presence of high environmental temperature, heat prostration (fever and heat stroke due to decreased sweating) can occur with use of Cantil (Mepenzolate bromide) .

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

Cantil (Mepenzolate bromide) may produce drowsiness or blurred vision. The patient should be cautioned regarding activities requiring mental alertness such as operating a motor vehicle or other machinery or performing hazardous work while taking this drug.

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

It should be noted that the use of anticholinergic drugs in the treatment of gastric ulcer may produce a delay in gastric emptying time and may complicate such therapy (antral stasis).

Psychosis has been reported in sensitive individuals given anticholinergic drugs. CNS signs and symptoms include confusion, disorientation, short-term memory loss, hallucinations, dysarthria, ataxia, coma, euphoria, decreased anxiety, fatigue, insomnia, agitation and mannerisms and inappropriate affect. These CNS signs and symptoms usually resolve within 12 to 24 hours after discontinuation of the medication.

Use Cantil (Mepenzolate bromide) with caution in the elderly (see ) and in all patients with:

Investigate any tachycardia before giving anticholinergic (atropine-like) drugs since they may increase the heart rate.

This product contains FD&C Yellow No. 5 (tartrazine), which may cause allergic-type reactions (including bronchial asthma) in certain susceptible individuals. Although the overall incidence of FD&C Yellow No. 5 (tartrazine) sensitivity in the general population is low, it is frequently seen in patients who also have aspirin sensitivity.

The following agents may increase certain actions or side effects of anticholinergic drugs: amantadine, antiarrhythmic agents of class I (e.g., quinidine), antihistamines, antipsychotic agents (e.g., phenothiazines), benzodiazepines, MAO inhibitors, narcotic analgesics (e.g., meperidine), nitrates and nitrites, sympathomimetic agents, tricyclic antidepressants, and other drugs having anticholinergic activity.

Anticholinergics antagonize the effects of antiglaucoma agents. Anticholinergic drugs in the presence of increased intraocular pressure may be hazardous when taken concurrently with agents such as corticosteroids. (See .)

Anticholinergic agents may affect gastrointestinal absorption of various drugs, such as slowly dissolving dosage forms of digoxin; increased serum digoxin concentrations may result. Anticholinergic drugs may antagonize the effects of drugs that alter gastrointestinal motility, such as metoclopramide. Because antacids may interfere with the absorption of anticholinergic agents, simultaneous use of these drugs should be avoided.

The inhibiting effects of anticholinergic drugs on gastric hydrochloric acid secretion are antagonized by agents used to treat achlorhydria and those used to test gastric secretion.

Clinical studies of Cantil (Mepenzolate bromide) did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range (see ), reflecting the greater frequency of decreased hepatic, renal or cardiac function (see ), and of concomitant disease or other drug therapy. (See .)

Cantil (Mepenzolate bromide) is contraindicated in intestinal atony of the elderly. (See .) Cantil (Mepenzolate bromide) should be used with caution in the elderly. (See .)

Precise frequency data from controlled clinical studies with Cantil (Mepenzolate bromide) are not available.

Tolerance, abuse, or dependence has not been reported with Cantil (Mepenzolate bromide) .

The usual adult dose is 1 or 2 tablets (25 or 50 mg) 4 times a day preferably with meals and at bedtime. Begin with the lower dosage when possible and adjust subsequently according to the patient's response.

Safety and efficacy in pediatric patients have not been established.

In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal or cardiac function, and of concomitant disease or other drug therapy. (See .)

25 mg mepenzolate bromide, compressed yellow tablets debossed MERRELL 37.

NDC 0068-0037-01: bottles of 100

Keep tightly closed. Store at room temperature, preferably below 86°F. Protect from excessive heat. Dispense in tight containers with child-resistant closure.