To eke out growth in one of the developed world's most sluggish pharmaceutical markets, Japanese drugmakers are turning to the pill-popping behavior of their customers.

Medication adherence is seen as an impediment to health as well as sales in Japan, and companies including Otsuka Pharmaceutical Co. and Eisai Co. are working with technology firms on compliance-boosting solutions — from treatment-sensing devices to automatic alerts sent via text message.

The strategy aligns with a worldwide drive for efficiency as drugmakers try to defend their profits from the cost-cuts sought by budget-strained health systems. In Japan, where an aging population has caused medical expenses to balloon, helping patients take medications as prescribed by their doctor may spur sales in a drug market predicted to expand at half the global pace over the next five years.