It is narrated from Sayyidah Aishah (may Allah be pleased with her): We would take the ritual bath while there was a plaster (on our hair), and we were with the Messenger of Allah (peace and blessings be upon him), both out of ihram and in ihram.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 860