Prompt: I told you not to touch it! from Madam'zelleG

A/N: Content warning for drug use, abuse and overdose. Apologies, because I have the feeling this could have been a lighthearted prompt, but I am an angst queen and this is where my brain took me. This is specifically set right before The Devil's Foot.

In looking over my records of the time I lived with Sherlock Holmes, the early months of 1897 stand out as extraordinarily busy, though for the unhappiest of reasons. It was, as I recall, an unusually mild winter in which Scotland Yard was kept busy by a number of unique and grotesque cases for which my friend's services were continually engaged. Weeks passed by that winter during which I hardly saw him, save for a quick word as he left me at the breakfast table, often already in disguise as either a common laborer, a sea captain, and once, as a liveried footman. My own affairs were no less busy, for there was a scarlet fever epidemic which required my attendance at multiple bedsides a day. Yet still, I took note of my friend's health as I had done for so many years, noting how little he seemed to eat and how much less he was sleeping.

"I cannot stop now, Watson," Sherlock Holmes said to me, once when I dared to remonstrate him about this. "I have only to prove that my client's brother was indeed at the meeting in Southwark at the time of the murder, or else he shall hang."

I could hardly argue with such a reason, yet when that case was brought to its completion, Detective Inspector Lestrade appeared almost immediately with another. All told, I believe I saw Holmes consume no more than four meals in a two month period, and the strains of his violin echoed up the stairs for hours nightly, so that I am sure he slept hardly more than four hours any given night. "Holmes, you must stop this," I said finally, one rare day where he seemed to be without a case. "You shall ruin your health." He ignored my worry, only sighing loudly and turning to stare into the fire. "Holmes!" I said.

"I am not your patient, Doctor!" Holmes said coldly, taking me slightly aback. "Has Inspector Lestrade called? I told him to keep me informed of the result of the Chambers case."

"He has not," I said, and Holmes sighed loudly. Fearing that he would sink into one of his black moods without something to occupy him, I said, "You were working on a monograph this morning. Why do you not pass the time by continuing it?" How he had managed to find any time to work on his own projects while he was so busy was remarkable to me, but as he was always happiest when he was working, I saw it as a lesser evil than forcing him to rest.

"Because there is no point," he said, rather melodramatically. "Watson, there is no one in the world who would read a monograph on the various types of restraints used in the detection and prevention of crime other than myself." He sat up and began pacing in front of our fire restlessly, waving his hands animatedly as he talked. "You see, it is all in the strength of the weave, at least, it is when dealing with rope. Handcuffs are an entirely different art, for there it is all in the type of lock. Locks are a study all their own, Watson, which was the subject of another monograph I wrote." He talked on like this for the next five minutes, while I simply watched in some amazement, for I do not believe I had ever seen him talk so excitedly. "So you see?" he asked, when he had finished. "What need have I to read my own monograph on the subject? There is nothing further I can learn from such a pointless exercise."

It was most unlike Holmes to even consider whether one of his pet projects had any practical use whatsoever, and I began to grow even more worried. My friend was always prone to drastic changes in his mood, and so far I had put it up to the strain of his workload. But in the last five minutes, his mood had shifted so wildly that a horrible suspicion formed in my mind. "Holmes," I said. "Look at me."

"Do bring your ministrations elsewhere, Doctor," he snapped, his mood shifting yet again. "I have told you before, I am perfectly well. Are you so poor a doctor that you cannot tell a healthy man when you see one?"

This outburst was most unlike Holmes, but I was only grieved by it rather than insulted, for it proved my suspicion correct. I am no expert at observation and deduction, but I knew my friend well. Ordinarily, during a lull in cases, he was overtaken by black moods that prevented him from getting up for days on end. His erratic behavior and excitability could only mean one thing: that he had once again engaged in cocaine, a habit I despised. I took a deep breath, dreading the confrontation we were sure to have - indeed, had already had so many times.

One of the benefits, however, of living with Sherlock Holmes is that he is quite capable of guessing what one is going to say. "Do not look so sanctimonious about my use of cocaine, Doctor. It is not illegal and is hardly more dangerous than tobacco, which I believe you are quite fond of yourself!" His eyes flashed and the look he gave me was one under which I had seen hardened criminals quail, though he no doubt knew it could hardly have the same effect on me.

"You know that you and I disagree on this subject," was all I said. I believed heartily that cocaine use was highly detrimental to one's health and thought that nothing could have greater benefit than if Her Majesty's government were to make it illegal. However, few even in the medical world believed the substance to be as dangerous as I did, not having had the dubious benefit of watching it destroy one of the country's greatest minds from the closest of viewpoints. Few who saw how Holmes changed under its influence could argue that its use was at all safe. I could not hide the hurt that engulfed me when I remembered his heartfelt words to me after his return to London, once we had apprehended Colonel Moran, that he would no longer need to indulge in his greatest vice. He had promised me he had given it up. Though I knew that once he craved the drug, it was far beyond his power to resist, I could not help feeling as if it was a betrayal. I stepped closer tentatively - one never knew what he would do while under the drug's influence, and while I did not believe he would strike me, it was best to be cautious. "Holmes," I said, once I was close enough to notice that his eyes were so dilated their usual grey was hardly visible. "How much did you take?"

"I have not overly indulged," my friend replied. "It is no more than my usual seven-per-cent solution."

I nodded in some relief. So at least he had not taken more than he was used to. I had once lived in fear of finding that he had overindulged, so I would at least be spared that for the moment. I went into the drawer where I knew the Moroccan case was kept and picked it up. I hdd pleaded and bargained with him for many years, and knew now that all I could do was remain firm in my resolve if I truly meant him to stop. "I will lock this up," I promised, "if I see you've touched it again, Holmes."

Holmes laughed. "Come, Watson, do you really think you are capable of hiding something so well I could not find it again?"

"No," I said. "But I am sure your brother could, and I will not hesitate to ask him."

Holmes's face suddenly grew cold. "You would not dare."

"Would you like to call my bluff?" I asked. "We have done this before, Holmes. If we do it again, it will be your choice." I had seen him come down off the drug before after long periods of use and it was something I would wish no one to go through, not even my worst enemy. I could only hope that I had caught him early enough that we could be spared that if he stopped now.

Holmes struggled to get himself under control, but I believe even he knew I was correct, and he calmed down enough to say, "Very well, Doctor," before ignoring me in anger for the rest of the day.

I very much wished I could take some time from my practice, now that I knew the danger, but the scarlet fever epidemic became a terrible strain of 'flu so that I was kept busy. I made sure to note Holmes's whereabouts whenever I knew them, noting for a few days that he had at least resumed eating and sleeping before running off on a new batch of cases. I did not know whether to wish there were fewer cases so that he might rest, or more so that he could be occupied and therefore leave aside the cocaine.

I had no suspicion that he had lied to me until a week after our confrontation. Holmes had been much like his usual self, apparently forgetting about our argument and discoursing to me about all subjects during those few times we had meals together. I dared to hope that it had been a one-time indiscretion until I chanced to return home earlier than expected to find him asleep on the settee in the middle of the day. This was most unlike him, and I am ashamed to say that rather than being pleased that he finally was getting some rest, I immediately checked to see if the Moroccan case had been opened. It did not appear as if it had, but even under the influence of the drug, Sherlock Holmes was still a formidable mind, and surely would have been capable of covering his tracks so that no one would notice he had used it. I waited until he at last awoke, and said only, "I told you not to touch it!"

His ashamed expression told me everything I needed to know.

I slept at my club that night and did not return until the next morning.

I said nothing, intending to go over to the Diogenes Club as soon as possible and ask for Mycroft's help in hiding the Moroccan case and its cursed syringe as soon as possible, when I was suddenly called to fill in at a nearby practice when one of the doctors who frequently took my practice while I was on a case fell ill. His practice was a busy one, and I found myself with not a moment of free time for nearly three days, after which I hastily returned to Baker Street, fearing the worst. "Holmes?" I cried, hurrying up the stairs.

I entered our sitting room to find my worst nightmare. Holmes was slumped on the floor next to the armchair and I rushed to his side, where he appeared to be unconscious. "Holmes!" I cried. I felt for his wrist, immensely relieved when I found his pulse, though it was racing and he appeared to be burning with fever. "Holmes, for God's sake, how much did you take?"

My friend groaned, and I managed to sit him up against the chair. "Watson?" he murmured thickly.

"Yes, I'm here," I said. "For heaven's sake, Holmes, I told you not to touch it," I added, though more in grief than remonstrance, now that I saw what condition he was in.

"I think I fainted," he said. "Not sure." He blinked and put a hand to his head. The Moroccan case was lying next to him, and I realized that he had never been so far gone before Never before had he forgotten to hide the evidence from me. "I am sorry, Watson," he said.

"Never mind, old fellow," I said. "I should not have left you alone, knowing what state you were in." I sighed in defeat. "This is beyond my ability, Holmes. You must allow me to call someone."

Perhaps even he realized what he had nearly done to himself, for he nodded, allowing me to support him to his bedroom. Once he was resting comfortably, I called Mrs. Hudson and instructed her to send for a doctor I knew, whose specialty was the effect various substances had on the body. "Do forgive me, Watson," Holmes said, his grey eyes glittering as I went back into his room. "I hardly meant to cause you any worry."

"I know, Holmes," I said tiredly. I was never used to seeing him vulnerable like this, though this was hardly the first time he had been laid up because of the drug. This was the only time it had been so close, though. I believe that if I had not found him he might be dead now. I sighed and looked him in the eyes. "Give up the cocaine, Holmes, for good, and there will be nothing to forgive," I said.

Silence, and then, "Very well, Watson. I will do what I must."