Motofen
Motofen is the brand name for an antiperistaltic anti-diarrheal medication, containing 1.0 mg difenoxin HCl and 0.025 mg atropine (US FDA: Schedule IV Combination).  Atropine is purposely added to minimize misuse potential since difenoxin is chemically related to the opiate family, and could theoretically be misused.  Although misuse or abuse is unlikely and rare, physical withdrawal symptoms may still be present if taken for long periods of time.  However, both of these compounds are responsible for the medicinal effects of the medicine (both atropine and difenoxin slow gut movement).
This combination medication should not be confused with Lomotil because the active ingredients in the two medications are different compounds, except for the inclusion of atropine.  Motofen is approximately 2 to 4 times more effective in treating symptoms than Lomotil (2.5 mg diphenoxylate and 0.025 mg atropine - Schedule V Combination.

# Indications and Uses
Although Motofen is officially indicated by the FDA for diarrhea, it has also been successfully used by physicians for irritable bowel syndrome (IBS), and hyperhidrosis (chronic, severe sweating).

# Side Effects, Interactions, and Misuse Potential
Side effects include (but are not limited to): drowsiness, nausea, vomiting, burning eyes, blurred vision, dry eyes, dizziness, dry mouth, epigastric distress, and constipation (a paradoxical side effect).  In addition to the side effects listed above, some are caused by the presence of atropine (especially when taken in excess doses, or in children), namely: flushing, dryness in many areas, urinary retention, insomnia, headache, anxiety, hyperthermia, and tachycardia.  It is these side effects produced by atropine, that makes it very undesirable for most patients to take higher amounts of the medicine.

# Dosing and Administration
Initial dosing states two tablets to be taken at first, and one tablet to be taken after each loose stool thereafter.  The recommended therapeutic dosage for Motofen should not exceed 8 tablets (8 milligrams of Difenoxin).  There are currently no instructions on use for Irritable Bowel Syndrome (IBS) and Hyperhidrosis, although as stated above, it has been used successfully in treating symptoms of both disorders (which can accompany each other).  There was a "Motofen half-strength" tablet, containing only .5 milligrams of Difenoxin (However, containing the same amount of atropine), but is now discontinued.  Therefore, only standard 1.0 milligram strength tablets are available by prescription.

# Availability, Price, and Supply
There is currently only one manufacturer of Motofen tablets: Valeant Pharmaceuticals. It acquired the drug from Amarin Pharmaceuticals in 2004.  Valeant's  tablets are pentagonal shaped, debossed with a "V" on one side, and vertically scored on the other side.  In addition, the number "0500" is debossed bisecting the score line perpendicularly.  The aforementioned debossing renders "05" and "00" on the left and right side of the score, respectively.
Motofen is higher priced than both Imodium and Lomotil, does not have a generic equivalent, and is only available by prescription in the United States (FDA).  Most United States insurance companies do not include Motofen as one of their formulary drugs, causing consumers to pay the highest copay, if it is covered by their health insurance at all.  The United States is currently the only country where Motofen tablets are prescribed, approved by the government, and sold.  This is most likely due to the high cost of the medication itself, and the fact that similar lower-priced medicines can help ease symptoms of diarrhea (However, Loperamide and Lomotil seem less effective in treating Irritable Bowel Syndrome and Hyperhidrosis patients, if effective at all).

# Misc. Information
Strangely, Motofen is only included in the Physicians' Desk Reference (PDR) for the years 2005 and 2006 as a literal snippet entry.  Nothing is said about the indications and usage, only the ingredients, current appearance (at the time of publishing), NDC#, and the quantities in which it is supplied.  It is still available though, and not very hard to find at pharmacies in decent sized metropolitan areas.  The pharmacist may not even know what it is, and is surprised to even find it on the shelf!