Kwells Tablets Kwells Tablets effectively prevent & control travel sickness in adults & children aged 10 & over. They melt in the mouth for rapid absorption into the bloodstream, so can be taken as little as 20-30 minutes before a journey, or at the onset of sickness. Kwells Tablets contain the active ingredient hyoscine hydrobromide, which temporarily reduces the effect of movement on the balance organs of the inner ear & the nerves responsible for nausea.