Limitations: This safety classification applies only to preparations containing a combination of the two drugs loperamide and dimeticone. This same ATC-code (A07DA53) may in some countries be used for different combinations of loperamide and other drugs which in theory may be porphyrinogenic. Please refer to the classification and monograph of each individual substance. Loperamide has not shown to alter the pharmacokinetics of other drugs and is not suspected to influence the activity of hepatic cyp enzymes in vivo. Dimeticone is a polymeric silicone devoid of Cyp-affinity and is not absorbed in the gastrointestinal tract.

Loperamide hydrochloride (chlorophenyl hydroxypiperidine dimethyl phenylbutylamide). One cyclic and one terminal tertiary nitrogen function. Simeticon (activated dimeticone; permethyl polysiloxane); Polymer with a structure of alternate atoms of silicon dioxide and liquid silicone. Practically insoluble in water. Water repellent, diminishing surface tension.

Loperamide in combination with dimeticone is indicated for the symptomatic treatment of acute diarrhoea with dyspepsia caused by abdominal disconfort and flatulence.

Not significant

About 40 per cent of the oral dose of loperamide is absorbed from the gastrointestinal tract. Substrate of P-gp. It is excreted as conjugates via bile, mainly or partly after Cyp3A4 and 2C8 oxidative conversion. Inhibition of CYP 3A4 has been shown in vitro but there are no drug interactions described with loperamide as perpetrator. Dimeticone is not absorbed from the gastrointestinal tract.

Uneventful use of this combination preparation is reported in 1 patient with acute porphyria. Also, loperamide in single ingredient preparations is reported to have been used uneventfully by 17 patients.