Marijuana can relieve pain, nausea and appetite loss — all potential symptoms of election season.

But the American Dental Association warns that dental appointments, like voting, are best met with a clear head.

Of 557 dentists surveyed, more than half said they'd had patients show up to appointments high on marijuana or drugs — and 56% reported limiting treatment as a result.

Almost half had to bump up anesthetic dosages to offset the joint effects of anesthesia and marijuana on the central nervous system.

Marijuana can boost anxiety, paranoia and hyperactivity, thereby raising stress levels.

It can also speed up heart rates and cause respiratory side effects that raise risks posed by local anesthetics.

Smoking marijuana is associated with head and neck cancers, gum disease and dry mouth, which can lead to oral health problems.