People always tip their heads way back when swallowing pills.

Tipping the head back opens the trachea and closes the esophagus, making it more difficult to swallow.

This action makes it obvious that the person is either actually swallowing a pill or wanting to make someone think they swallowed it.

CPR almost always works.

In controlled situations (e.g. in a hospital) administering CPR will improve a patient's chances of surviving until proper medical attention can be administered. In other situations, especially if the incident wasn't immediately noticed, the chances of survival are quite low, only a few percent (but still very worth the effort). Having the patient regain consciousness while receiving CPR is very rare.

CPR is very dramatic and suspenseful, and why shouldn't this particular case be one of the 1%?

Defibrillators can restart completely stopped hearts.

Defibrillators are used to correct hearts that are beating irregularly or too quickly. They are not used if the heart is no longer beating. More extreme medical intervention is required for that.

Using these devices is very dramatic, so why shouldn't they be used to restart a dead person's heart?

A huge needle directly through the chest into the heart will restart it.

Intracardiac injection used to be a method of getting medication directly into a patient's heart. The technique hasn't been used since the 1970s, as it had proven to be no more effective than using much less dangerous means of injecting medicine into the bloodstream.

What could be more dramatic than having a huge needle slammed into the chest of a dead character, who immediately sits up and gasps for breath?

Blows to the head can be precisely delivered to cause specific periods of unconsciousness.

Loss of consciousness is a symptom of concussion and brain injury. Sometimes large blows do not cause injury or loss of consciousness. Sometimes small blows can be fatal. The effects cannot be predicted; and definitely not with any precision or accuracy.

Sometimes characters need to be eliminated or put out of action for a while. Most good guy characters aren't allowed to kill or cause permanent injury to anyone, so they use gentle 5 minute taps or harder for an hour taps to temporarily remove the character from the action.