What decreased alertness, slurred speech, drowsiness, and depressed respiration are common side effects of what ?

The correct answer is - depressants.

Explanation:

Depressants are drugs that lower the neurotransmitters levels, that is used to reduce the stimulation or arousal. These drugs inhibit the activity of CNS function in some parts of the brain.

These drugs lead to several symptoms like less alertness, drowsiness, sleepy, and decreased inhibition as they affect the neurons of CNS.

Long term use of the depressants can cause depression, sleep problems, chronic fatigue, anxiety, panic attacks slurred speech and many more.

Thus, the correct answer is - depressants.

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