Some psychoactive drugs can also affect the functions of the autonomic nervous system. Amphetamines, which are commonly prescribed to treat ADHD, can lead to elevated heart rates and increased arousal. References: 1  American Psychological Association. 2  APA concise dictionary of psychology.
If you are sick with strep throat, you will be contagious until you have been on antibiotics for at least 24 hours. However, your symptoms may last longer than that. It is important to take all of your antibiotics as prescribed.
Tonsillitis can also be caused by bacteria, usually the same bacteria that cause strep throat (streptococcus group A). A person with tonsillitis caused by strep bacteria is contagious early on and without treatment can remain so for up to two weeks.