According to the sunnah, there are days which are more beneficial to have hijama treatment done. These dates are mentioned in the narration below:
‘Whoever performs cupping on the 17th, 19th or 21st of the islamic lunar month, then it is a cure for every disease.’ -(Abu Dawood)
Prophet Muhammad (PBUH) said: “Those who have cupping on the 17th, 19th and 21st day (of the Islamic lunar month) will be cured from every disease.” [Abu Dawud 3861] Cupping is preferred in the third quarter and latter part of the lunar month. However, if cupping is necessary, it will be useful during any part of the month including the beginning and the end.