Breast-feeding

Guaifenesin is excreted in breast milk in small amounts. There is insufficient information on the effects of Guaifenesin in newborns/infants. A decision must be made whether to discontinue breast-feeding or to discontinue/abstain from Guaifenesin Cough Menthol flavour 100 mg/5 ml Oral Solution therapy, taking into account the benefit of breast feeding for the child and the benefit of therapy for the woman.

Fertility

There is insufficient information available to determine whether guaifenesin has the potential to impair fertility.

4.7 Effects on ability to drive and use machines
Guaifenesin has no or negligible influence on the ability to drive and use machines.

4.8 Undesirable effects
The following side effects may be associated with the use of guaifenesin:

Immune System Disorders: Hypersensitivity reactions including pruritus and urticaria, rash (frequency – not known).

Gastrointestinal disorders: Abdominal pain upper, diarrhoea, nausea, vomiting (frequency – not known).

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
4.9 Overdose
Symptoms and signs

The symptoms and signs of overdose may include gastro-intestinal discomfort, nausea and drowsiness.

When taken in excess, guaifenesin may cause renal calculi.

Treatment

Treatment should be symptomatic and supportive.

5. Pharmacological properties
5.1 Pharmacodynamic properties
ATC Code: R05CA03; Pharmacotherapeutic Group: Cough and Cold Preparations, Expectorants

Guaifenesin is thought to exert its pharmacological action by stimulating receptors in the gastric mucosa. This increases the output from secretory glands of the gastrointestinal system and reflexly increases the flow of fluids from glands lining the respiratory tract. The result is an increase in volume and decrease in viscosity of bronchial secretions. Other actions may include stimulating vagal nerve endings in bronchial secretory glands and stimulating certain centres in the brain, which in turn enhance respiratory fluid flow. Guaifenesin produces its expectorant action within 24 hours.

5.2 Pharmacokinetic properties
There is no information available on the pharmacokinetics of guaifenesin in special populations.

Absorption

Guaifenesin is well absorbed from the gastro-intestinal tract following oral administration, although limited information is available on its pharmacokinetics. After the administration of 600 mg guaifenesin to healthy adult volunteers, the Cmax was approximately 1.4 ug/ml, with tmax occurring approximately 15 minutes after drug administration.

Distribution

No information is available on the distribution of guaifenesin in humans.

Metabolism and elimination

Guaifenesin