Studying the effect of psychedelic substances on expression of creativity is a challenging problem. Our primary objective was to study the psychometric measures of creativity after a series of ayahuasca ceremonies at a time when the acute effects have subsided. The secondary objective was to investigate how entoptic phenomena emerge during expression of creativity. Forty individuals who were self-motivated participants of ayahuasca rituals in Brazil completed the visual components of the Torrance Tests of Creative Thinking before and the second day after the end of a two-week long ceremony series. Twenty-one comparison subjects who did not participate in recent psychedelic use also took the Torrance tests twice, two weeks apart. Repeated ingestion of ayahuasca in the ritual setting significantly increased the number of highly original solutions and phosphenic responses. However, participants in the ayahuasca ceremonies exhibited more phosphenic solutions already at the baseline, probably due to the fact that they had more psychedelic experiences within six months prior to the study than the comparison subjects did. This naturalistic study supports the notion that some measures of visual creativity may increase after ritual use of ayahuasca, when the acute psychoactive effects are receded. It also demonstrates an increased entoptic activity after repeated ayahuasca ingestion.