4 combinations of preparations that can be lethal

Some adult people hold multiple drug prescriptions. In some cases the wrong combo could have critical consequences, says epidemiologist Dr. Leonard Paulozzi. Beware these potentially toxic matches, and always ask your doctor before mixing.

SSRIS + Opioids

(antidepressants + painkillers)

Some antidepressants work by increasing brain levels of the "happy hormone" serotonin. Certain painkillers can have the same effect—leading to way too much of a good thing. Sky-high serotonin levels can cause agitation, high body temperature, and rapid heart and breathing rates.

Opioids + Benzodiazepines

(painkillers + anti-anxiety meds)

Both types of drugs act as depressants, which can spell sweet relief if you're super anxious or in serious pain—or super anxious about being in serious pain. But the pills can also lower heart and breathing rates, sometimes too much.

Statins + Fluconazole

(cholesterol-lowering drugs + antifungal medication)

Anyone who's had a yeast infection is likely familiar with fluconazole. And statins are among the world's most prescribed drugs, making this a highly likely duo that could cause muscle weakness or kidney damage.

Opioids + Benzodiazepines + Carisoprodol

(painkillers + anti-anxiety meds + muscle relaxers)

Most M.D.'s know this combo could turn deadly.