Some antibiotics can make people get strange feeling. A lot of the time it is short lived, like 24 hours. Here is a list of side effects from this site:
http://www.drugs.com/zithromax.html
Zithromax side effects
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have a serious side effect such as:
diarrhea that is watery or bloody;
chest pain, uneven heartbeats;
nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes); or
fever, sore throat, and headache with a severe blistering, peeling, and red skin rash.
Less serious side effects may include:
mild nausea, vomiting, diarrhea, constipation, or stomach pain;
dizziness, tired feeling, or headache;
nervous feeling, sleep problems (insomnia);
******l itching or discharge;
mild itching or skin rash;
ringing in your ears, problems with hearing; or
decreased sense of taste or smell.
This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect.