Government travel advice has been updated to urge British tourists in Spain to use balconies safely.
The Foreign Office (FCO) said there had been a number of "very serious accidents" as a result of falls from balconies and popular craze "balconing".
The practice involves jumping off a balcony into a swimming pool.
Three balcony falls resulting in serious injury were reported to the FCO earlier in 2016, travel trade organisation Abta said.
The figure represents "just a fraction of the total number of incidents", the organisation added.
The updated advice, published on the FCO website, states: "There have been a number of very serious accidents (some fatal) as a result of falls from balconies.
"Many of these incidents have involved British nationals under the influence of drink or drugs.
"Your travel insurance may not cover you for incidents that take place while you're under the influence of drink or drugs."
It adds: "Some local councils will impose fines to those caught behaving irresponsibly on balconies or practising 'balconing'."