WIth a heat wave gripping much of the nation this week, experts are warning people who take certain medications to be careful.  

Those include medicines for high blood pressure, allergies and mental health.  Diuretics, which help the body produce more urine, can lead to dehydration in extreme heat.  

Beta blockers can impede the body's ability to regulate temperature, while certain antipsychotics can affect the ability to produce sweat.