Appearance
Drugstore beetles range in size from 1/10 of an inch to 1/7 of an inch, about the size of a ladybug. The shell is brown or reddish brown with a characteristic deep groove or cleft running down the length of the shell between the wing cases. The combination of this groove and the beetle's coloration causes many people to compare them to coffee beans while seeking identification. The drugstore beetle resembles the less common cigarette beetle in most respects, though they can be set apart by their antennae: the cigarette beetle's are clubbed, while the drugstore beetle's are serrated.
Diet
Drugstore beetles are most often found in the kitchen, where they are capable of infesting a wide variety of dry goods. Dog food, flour and grain are some of their favorite targets, although their diet has been wryly defined as "anything but cast iron." In fact, their name comes from their habit of devouring prescription drugs. They are capable of chewing through packaging or even aluminum foil to get at food. They are less commonly encountered in other rooms of the house, where they often attack the paper in books and newspapers.
Prevalence
Drugstore beetles and cigarette beetles are encountered worldwide, although drugstore beetles are more common in temperate zones and cigarette beetles are more common in the tropics. They are not typically capable of surviving temperate winters outside, but any heated facility provides them with a year-round habitat. They are considered serious commercial pests, especially in industries that deal with grain or flour.
Pest Control
Since drugstore beetles are pantry pests, pesticides are more difficult and risky to apply without contaminating stored food. The best way to deal with a drugstore beetle infestation is locating and disposing of infested food and storing your food in air-tight metal, plastic or glass containers. Most store packaging will not keep carpet beetles out of your food. Once your food is stored in sealed containers, clean up any spills or residues that may attract reinfestation. If these steps fail, applying pesticide to the baseboards and cabinets of a kitchen will quickly wipe out an infestation, although it may not stop a new infestation if the food source is not taken care of.