bur·den·some 
(bûrdn-səm)
(bûrdn-səm)adj.
1. Weighing much or hard to carry; heavy.
2. Causing hardship or distress.
burden·some·ly adv.
burden·some·ness n.
Synonyms: burdensome, onerous, oppressive, weighty
These adjectives apply to what causes one to feel weighed down, as with duties, difficulties, or hardships: the burdensome task of preparing a tax return; the onerous chores involved in maintaining a large house; oppressive policies that restricted citizens' freedom; the weighty concerns that troubled the jurors.
These adjectives apply to what causes one to feel weighed down, as with duties, difficulties, or hardships: the burdensome task of preparing a tax return; the onerous chores involved in maintaining a large house; oppressive policies that restricted citizens' freedom; the weighty concerns that troubled the jurors.