| Kali phos. has a great action on the nervous system. Students and others suffering from depression and exhaustion after prolonged intellectual work can benefit from this remedy. The brain fatigue leads to loss of memory , headaches in school children (also relieved by Calc. phos.) and a feeling of physical as well as mental exhaustion. So it is great for ailments from overstudy, as well as for ailments from nightwatching (like Cocculus), where the person has lost a lot of sleep while taking care of an ill family member or friend.