This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pharmacology, Subject name: Pharmacology
Which of the following drug is excreted in saliva? 
Select and explain. 
A. Tetracyclines, B. Ampicillin, C. Lithium, D. Chloramphenicol
C: Lithium
Answer: C: Lithium 
Explanation: Saliva and sweat are of minor impoance for drug excretion. Lithium, potassium iodide, rifampin, and heavy metals are present in sweat and saliva significant amounts saliva levels of lithium can be estimated in case of poisoning Ref; KD Tripathi pharmacology 7th edition (page no; 28)