The safety of loperamide hydrochloride was evaluated in 3076 adults and children aged ≥ 12 years who participated in 31 controlled and uncontrolled clinical trials of loperamide hydrochloride used for the treatment of diarrhoea. Of these, 26 trials were in acute diarrhoea (N=2755) and 5 trials were in chronic diarrhoea (N=321).
The most commonly reported (i.e., ≥ 1% incidence) adverse drug reactions (ADRs) in clinical trials with loperamide hydrochloride in acute diarrhoea were: constipation (2.7%), flatulence (1.7%), headache (1.2%) and nausea (1.1%). In clinical trials in chronic diarrhoea, the most commonly reported (i.e., ≥ 1% incidence) adverse reactions were: flatulence (2.8%), constipation (2.2%), nausea (1.2%) and dizziness (1.2%).
Table 1 displays adverse reactions that have been reported with the use of loperamide hydrochloride from either clinical trials (in acute or chronic diarrhoea or both) or post-marketing experience.
The frequency categories use the following convention: very common (>1/10); common (>1/100 to <1/10); uncommon (>1/1,000 to <1/100); rare (>1/10,000 to <1/1,000); and very rare (<1/10,000).
Table 1: Adverse Reactions
System Organ Class | Adverse Reaction |
Common | Uncommon | Rare | Not known |
Immune System Disorders | | | Hypersensitivity reaction, Anaphylactic reaction (including Anaphylactic shock), Anaphylactoid reaction | |
Nervous System Disorders | Headache, Dizziness | Somnolence | Loss of consciousness, Stupor, Depressed level of consciousness, Hypertonia, Coordination abnormality | |
Eye Disorders | | | Miosis | |
Gastrointestinal Disorders | Constipation, Nausea, Flatulence | Abdominal pain, Abdominal discomfort, Dry mouth, Abdominal pain upper, Vomiting, Dyspepsia | Ileus (including paralytic ileus), Megacolon (including toxic megacolon – see section 4.4), Abdominal distension | Acute Pancreatitis |
Skin and Subcutaneous Tissue Disorders | | Rash | Bullous eruption (including Stevens Johnson syndrome, Toxic epidermal necrolysis and Erythema multiforme), Urticaria, Pruritus, Angioedema | |
Renal and Urinary Disorders | | | Urinary retention | |
General Disorders and Administration Site Conditions | | | Fatigue | |
A number of the adverse reactions reported during the clinical investigations and post-marketing experience with loperamide hydrochloride are frequent symptoms of the underlying diarrhoeal syndrome (for example abdominal pain/discomfort, nausea, vomiting, dry mouth, tiredness, drowsiness, dizziness, constipation, and flatulence). These symptoms are often difficult to distinguish from undesirable drug effects.
Paediatric population
The safety of loperamide hydrochloride was evaluated in 607 patients aged 10 days to 13 years who participated in 13 controlled and uncontrolled clinical trials of loperamide hydrochloride used for the treatment of acute diarrhoea. In general, the adverse reactions profile in this patient population was similar to that seen in clinical trials of loperamide hydrochloride in adults and children aged 12 years and over.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at www.mhra.gov.uk/yellowcard.