Aleksei was apparently given morphine in 1917, but the cause is unknown:
At any case, just to clarify the cause. In E. Naryshkina's diary we find the following quotations:
29. 01.1917 “The little one has fallen ill. New alarm for the Empress!”
1. 02 “I learned that the heir was ill more seriously as we thought. I can imagine the emotion of the Empress, after Grigory’s disappearance. It seems that he (the heir) had a awkward movement and his illness transport to his back.”
Although it does not concern stomach and kidney problems, it is perhaps interesting to say that the first months of 1917 were especially bad for Alexei Nikolaevich. We all know about measles. But we should remember that before this he was almost all the time in bed since the 18th January. I have made a chronology of his illness, using diaries of NA and AF, and other documents. All come from the russian edition of the diaries. If it is not the right place for it, the moderator will delete my post, that will be all right.
Diary A 18.01.1917: “Sat with Al (…) Al 6 hours 38,7. Then: “Sat with Al 38,4”
Diary N 18.01.1917: “Alexei had ill tonsils, he stayed the whole day in bed”
A. 19.01: “Al 37,5. Sat with Al before lunch (…) Al 9 hours 38”
A. 20.01 Al 36,6. Sat with him 11.40 – 1.pm (…) Sat with Al until 4pm Al 9 pm 37,5
A. 21.01 Al 36,2, sat with him (…)Sat with Al. Al 36,6
A. 22.01 36,1 (…) Sat with Al
N. 22.01 Stayed with Alexei.
A. 23.01 Al 36,6 (…) Stayed with Al
A. 24.01 Stayed with Al
A. 25.01 Stayed with Al (…) Al 37,2 (…) Al 36,7
A. 26.01 Stayed with Al
A. 27.01 Stayed with Al (…) Stayed with Al, O, T, A, daughters (…) Al 37, 1
A. 28.01 Came to Al upstairs (…) On the balcony with A(nia) and Al
A. 29.01 2.30 pm – 4.30 pm. Stayed with Al
Naryshkina: 29. 01“The little one has fallen ill. New alarm for the Empress!”
N. 29.01: Stayed with Alexei before tea.
A. 30.01: Stayed with Al (…) Stayed with Al
N. 30.01: Stayed with Alexei before tea
A. 31.01: Stayed with Al (…) Stayed with Al (…) Read to Al.
N. 31.01: Came to Alexei.
A. 1.02: Stayed with Al. Fedorov (…) Stayed with Al
Naryshkina 1.02: “I learned that the heir was ill more seriously as we thought. I can imagine the emotion of the Empress, after Grigory’s disappearance. It seems that he (the heir) had a awkward movement and his illness transport to his back.”
A. 2.02: Stayed with Al
A. 3.02: Stayed with Al (…) Stayed with Al.
A. 4.02: Stayed with Al (…) Read to Al
A. 5.02: Stayed with Al
A. 6.02: Stayed with Al
N. 06.02: Stayed with Alexei, as usual before going for a walk
A. 07.02: Stayed with Al
A. 08.02: Stayed with Al (…) The Hakham was by Al (a Crimean tatarian dignitary)
A. 09.02: Had lunch in bed then went upstairs to Al (…) After dinner read to Baby
A. 10.02: Came to Al and Olga (Olga have an ear inflammation)
A. 11.02: With Olga and Alexei (...) Stayed with Al (…) Read to Al. O.
N. 11.02: Came upstairs to Olga and Alexei who were lying afternoon in the one room.
A. 12.02: Stayed with Al and Olga. His 2 cadets, Makarov, A(geev)
A. 13.02: Stayed with Al
N. 13.02: Came upstairs to Olga and Alexei
A. 14.02: Stayed with O and Al. Al get up from hid bed for the first time
N. 14.02: Alexei get up afternoon
A. 15.02: Stayed with O and Al
A. 16.02: Stayed with O and Al (…) Stayed with Al, O and M(aria)
N: 16.02: Stayed with Olga, Maria and Alexei
A. 17.02: Al had lunch with together with us for the first time
A. 18.02: Holly communion. At 11.30 O, M and Al received it in Baby’s bedroom (…) Read to Al
Naryshkina 18.02: “Had communion together with the Sovereign, the Empress and 2 GD. The others have not yet recovered. The heir is better, but he does not go outside.”
19.02 There was a séance of cinema in the Round room. All the children, apart Olga were present.
A. 20.02: Stayed with the children upstairs.
A. 21.02: Stayed with Al and O
N. 21.02: Stayed upstairs with Olga and Alexei who feel themselves better
A. 22.02: Al 38,3
A. 23.02: O and Al have measles