Oct 19 (Reuters) - Swiss online drug retailer DocMorris on Thursday narrowed down the higher end of its annual core loss forecast, citing weaker development in the paper prescription business.

It sees adjusted core loss of 30 million to 40 million Swiss francs ($33.4 million to $44.5 million) in 2023, compared to the previous range of 20-40 million.

The company, which relies heavily on the German market since it sold its Swiss business to Migros earlier this year, still aims to become profitable in 2024. This target does not take into account a positive effect of e-prescriptions, which were rolled out across Germany in July.

DocMorris also cut its 2023 external revenue outlook, expecting a high single-digit percentage decline in local currency, from a previously expected mid-single-digit drop.

Its external revenue fell 5.8% to 256 million Swiss francs in the third quarter, below the 262 million francs expected by analysts polled by the company. ($1 = 0.8990 Swiss francs) (Reporting by Tristan Veyet and Mateusz Dobrzyniewski in Gdansk; editing by Milla Nissi)