(1) Caffeine also leads to headaches, jitteriness, agitation, stomach problems and abnormal breathing.

(2) Unpleasant side effects, including headache and jitteriness , among others, were reported by roughly half of the users.

(3) Half of the drug-takers reported such effects, including headaches, jitteriness, anxiety and sleeplessness.

(4) But too much can increase heart rate, blood pressure, and jitteriness.

(5) What's more, as users chase the caffeine buzz, their intake climbs--sometimes to 1, 200 mg a day or more, leading to jitteriness and sleeplessness.

(6) Modafinil can keep a person awake and alert for 90 hours straight, with none of the jitteriness and bad concentration that amphetamines or even coffee seem to produce.

(7) Potential side effects of light therapy are rare and most often include jitteriness , a feeling of eyestrain and headache.

(8) We found a negative correlation between a star's metallicity and its jitteriness.

(9) Meltdown is also designed to increase mental clarity and mood with minimal jitteriness while burning fat at an unprecedented rate.