Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Call emergency services now if someone exposed to paradichlorobenzene has:
Elsewhere, use the local poison information service or emergency number.
And for anyone, someone who:
Contact a poison center promptly after any known or possible swallowing of a mothball or deodorizer block.
Also call after a substantial exposure in an enclosed space, an exposure involving a child, or repeated intentional exposure.
In the United States, Poison Control is available at 1-800-222-1222.
Arrange prompt medical assessment for persistent headache, nausea, unusual tiredness, dark urine, jaundice, poor balance, tremor, memory changes, or personality changes after repeated exposure.
Routine follow-up is important after diagnosed poisoning, even when you feel better.
Blood, liver, kidney, or neurological changes may need monitoring until they improve or become stable.
Every sign above is quoted from the sofidex article on Paradichlorobenzene poisoning. If you are not sure, err upward — it is always reasonable to be checked.