What are synonyms of lethargy?

Here are some synonyms for lethargy, categorized by nuance:

General Tiredness and Lack of Energy:

* Fatigue

* Exhaustion

* Weariness

* Lassitude

* Listlessness

* Enervation

* Debilitation

* Languor

Sluggishness and Slowness:

* Inactivity

* Torpor

* Dullness

* Apathy

* Indolence

* Sluggishness

* Phlegm

* Heaviness

Mental Slowness:

* Drowsiness

* Stupor

* Somnolence

* Dullness

* Fogginess

* Cloudiness

More Formal or Medical:

* Malaise

* Adynamia

* Asthenia

Informal:

* Dead tired

* Busted

* Drained

* Run down

The best synonym to use will depend on the specific context and the desired level of formality.