Sixth house is the house of enemies, debts, disease and of service. Placement of Mercury may not be ideal in house of enemies. Mercury is smart and loves a good argument but hates physical fights. Sixth house is the house of enemies, wars and competition. Mercury would rather try diplomatic and peaceful solution by discussing issues. Ofcourse lawyers, diplomats and negotiators may benefit from a strong Mercury in sixth house.

• North Style
• South Style

     According to B. V. Raman: "Mercury in the sixth house makes the native quarrelsome and a showoff. Yet he/she is respected and feared by enemies. If afflicted with malefic planet there is every chance of having a nervous breakdown or mental troubles. This placement also makes a native lazy and somewhat harsh in speech". Mercury hates physical confontration but loves verbal duels. That is why it is essential that natives choose a career which favors verbal arguments like lawyer, news panelists or role as crisis negotiator. Sixth house also rules debts and disease. Mercury has excess of earth element so indigestion and acidity are likely. Mercury also rules over skin, nervous system and speech. And problems related to them are a possibility.

     With planets like Sun or Mars as co-tenants native maybe argumentative but he can have a good career in communication, marketing, management or sports related fields. With Rahu or Ketu there maybe nervous breakdown once in a while. Mercury with Jupiter could be great for post of a diplomat or deal broker but not so good for health as this may promote obesity and indigestion. Mercury with Venus could promote lustful activities and there are chances of catching a venereal disease. Native could also be a drug addict or even addicted to medical pills. On the bright side native with Mercury+Venus in sixth house can have a decent career as a dancer or a musician. Mercury with Saturn could be great for service in software sector. Mercury with Moon is good for jobs in catering and communication but bad for mental health.

     Mercury is largely favorable in the sixth house. Those who have nervous disorders or mental troubles are advised to pray to Lord Vishnu or Lord Ganesha. Eating Mung Bean(Vigna Radiata) in abundant quantity might be good for mind as well as stomach. Its a good idea to eat light meal at night especially for those who suffer from digestion problems. Avoid arguments with others if it leads to bad relation or physical confontration.

References:

Raman, Bangalore Venkata. How to Judge a Horoscope. Delhi: Motilal Banarsidass, 2014. Print.