Papyrus Leiden I 343 + 345 is one of the most extraordinary manuscripts providing a deeper insight into magic and medicine in Ancient Egypt. The main part of the papyrus deals with the ancient Near Eastern disease demon S¿m¿nu, who is well known from Sumerian and Akkadian incantations and medical texts. In addition, a broad range of other conjurations and spells against any pain and feet swelling are included. The papyrus also contains two curious spells dealing with ¿falling water from the sky¿. Eight out of fourteen incantations against the demon S¿m¿nu were incorporated twice in this papyrus. The texts are not only presented as parallel text edition but also with photographs of the papyrus. This re-edition of papyrus Leiden I 343 + 345 is a revised transliteration, transcription, translation and up-to-date commentary. Contents I Introduction 1 Origin and date 2 Bibliography 3 Description of the manuscript 4 Reconstruction of the papyrus in its original form 5 Content 6 Language and grammar 7 Importance of the text II Text with transliteration, translation and commentary 1 Incantation 1 (R:I1¿I4/V:II4¿II10) 2 Incantation 2 (R:I4¿III2/V:III1¿IV8) 3 Incantation 3 (R:III2¿IV9/V:V8¿VII5) 4 Incantation 4 (R:IV9¿VI2/V:VII5¿VIII12) 5 Incantation 5 (R:VI2¿VIII9/V:XI, XII, XIII) 6 Incantation 6 (R:VIII10¿X9/V:XIV, XV) 7 Incantation 7 (R:X9¿XI1/V:XVI1¿2) 8 Incantation 8 (R:XI2¿14/V:XVII) 9 Fragments recto (R:XII¿XXII1) 10 Incantation 9 (R:XXII1+x+1¿2) 11 Fragments recto (R: XXIIIx+1¿XXV1+ x+2) 12 Conjuration 1 and remedies 1¿4 (R:XXV1+x+2¿XXVI12) 13 Conjuration 2¿3 (R:XXVI12¿XXVIII5) 14 Incantation 10 (V:I1¿8) 15 Incantation 11 (V:I8¿II3) 16 Incantation 12 (V:IV9¿V8) 17 Incantation 13 (V:IX1¿X2) 18 Fragments verso (V:XVIII1¿XXI3) 19 Incantation 14 (V:XXII1¿3) 20 Conjuration 4 (V:XXII3¿4) 21 Conjurations 5 and 6 (?) (V:XXIII1¿XXIV6) 22 Spells 1¿3 (V:XXV) Appendix I: Glossary Appendix II: Present appearance of the papyrus Abbreviations Bibliography Indices Sketch of Papyrus Leiden I 343 + I 345 Plates