If you are suffering from a persistent headache, don’t be tempted to eat mothballs. In 2011, a 34-year old patient was admitted (unconscious) to a hospital emergency department in Amsterdam “following the ingestion of camphor mothballs for persisting headaches”.
Fortunately, after a week or so of intensive clinical care she recovered and was discharged in good clinical condition (apart from some apparent memory loss). See: Kamferintoxicatie na inname van mottenballen ‘wegens hoofdpijn’ (in Dutch) in: Nederlands Tijdschrift Voor Geneeskunde [01 Jan 2011, 155(39):A3676]. An extended extract of the study can be found here (in English).
Note: Mothballs, which can contain camphor, naphthalene, 1,4-dichlorobenzene and other highly toxic chemicals should never be ingested for any reason.