Shiva remains in divine intoxication.
Hence, his association with dhatūra or thorn-apple...which has hallucinogenic properties.
Dhatūra is called shiva-shekhara, the crown of Shiva.
It is believed to have emerged from Shiva’s chest after he drank the deadly poison, halahal, produced during the churning of the cosmic ocean.
Its leaves and fruit are offered to Shiva on special days.

The above is a quotation from a contemporary article devoted to Hindu liturgical practice and provides a rationale for the presentation of plant parts (often seed capsules) of Datura metel to the deity Shiva, integrated (no later, on evidence currently available, than the second century C.E.) into a much older mythological framework dating back to Vedic times.

The Vedic myth referenced is that of The Churning of the Ocean of Milk (Sanskrit Samudra manthan), in which two groups of gods, the Devas and the Asuras, churn the Cosmic Ocean of Milk (Sanskrit Kshira Sagara) to bring forth treasures.
In the course of the churning, the terrible, choking poison Halahala emerges from the ocean before the treasures and threatens to overwhelm the cosmos.

Only the god Shiva is strong enough to swallow the poison, thus neutralising it, and, even in so doing, still requires the help of his consort, the goddess Parvati, who squeezes his throat to trap the poison there.
Such is the potency of the poison that, even though Shiva is able to transmute it to make it harmless, it turns his throat permanently blue, so that, ever afterward one of his epithets has been Neelakanta - "the blue-throated one".
Shiva remains in divine intoxication. Hence, his association with dhatūra or thorn-apple...which has hallucinogenic properties. Dhatūra is called shiva-shekhara, the crown of Shiva. It is believed to have emerged from Shiva’s chest after he drank the deadly poison, halahal, produced during the churning of the cosmic ocean. Its leaves and fruit are offered to Shiva on special days.
The above is a quotation from a contemporary article devoted to Hindu liturgical practice and provides a rationale for the presentation of plant parts (often seed capsules) of Datura metel to the deity Shiva, integrated (no later, on evidence currently available, than the second century C.E.) into a much older mythological framework dating back to Vedic times.
The Vedic myth referenced is that of The Churning of the Ocean of Milk (Sanskrit Samudra manthan), in which two groups of gods, the Devas and the Asuras, churn the Cosmic Ocean of Milk (Sanskrit Kshira Sagara) to bring forth treasures. In the course of the churning, the terrible, choking poison Halahala emerges from the ocean before the treasures and threatens to overwhelm the cosmos.
Only the god Shiva is strong enough to swallow the poison, thus neutralising it, and, even in so doing, still requires the help of his consort, the goddess Parvati, who squeezes his throat to trap the poison there. Such is the potency of the poison that, even though Shiva is able to transmute it to make it harmless, it turns his throat permanently blue, so that, ever afterward one of his epithets has been Neelakanta - "the blue-throated one".
Datura metel