When smoked or vaporised, THC passes quickly through the lungs into the blood. The effect starts almost immediately.
When eaten or drunk, for example in biscuits or tea, THC first has to pass through the stomach, gut and liver. The effect therefore comes on with a delay and often suddenly. In a study with adults, it only peaked after one and a half to three hours and lasted six to eight hours. In children under six, it usually lasts more than eight and up to 24 hours (both according to ToxInfo).
The problem: anyone who still feels nothing after an hour and takes more gets the effect of both portions almost at the same time. This leads to overdoses with anxiety, panic and severe nausea.
Edibles are particularly dangerous for children. Edibles look like normal sweets, and even small amounts can lead to serious poisoning. So always store them safely and out of children’s reach. If a child has eaten some, call the poison information centre: in NRW, that is the Informationszentrale gegen Vergiftungen Bonn on 0228 19240, around the clock. In the event of unconsciousness, breathing difficulties or a seizure, call 112 immediately.
In Germany, edibles are banned. Cultivation associations may only pass on cannabis as flowers or hashish (§ 19 para. 1 KCanG), and manufacturing cannabis is prohibited (§ 2 para. 1 no. 3 KCanG).
Remember: With edibles, do not take more; wait instead. And always keep them out of the reach of children.
More on this: Edibles: the risks and why they are banned · What cannabis does in the body · Home and children