Medicine loves guidelines. But everywhere else, guidelines are still underappreciated. Consider a recommendation, like “Try Lexapro!” Even if Lexapro is a good medication, it might not be a good medication for your situation. And even if it’s a good medication for your situation, it might fail for unpredictable reasons involving genetics and individual variability. So medicine uses guidelines – algorithms that eventually result in a recommendation. A typical guideline for treating depression might look like this (this is a very over-simplified version for an example only, NOT MEDICAL ADVICE): 1. Ask the patient if they have symptoms of bipolar disorder. If so, ignore everything else on here and move to the bipolar guideline. 2. If the depression seems more anxious, try Lexapro. Or if the depression seems more anergic, try Wellbutrin. 3. Wait one month. If it works perfectly, declare victory. If it works a little but not enough, increase the dose. If it doesn’t work at all, stop it and move on to the next step. 4. Try Zoloft, Remeron, or Effexor. Repeat Step 3. 5. Cycle through steps 3 and 4 until you either find something that works, or you and your patient agree that you don’t have enough time and patience to continue cycling through this tier of options and you want to try another tier with more risks in exchange for more potential benefits. 6. If the depression seems more melancholic, try Anafranil. Or if the depression seems more atypical, try Nardil. Or if your patient is on an earlier-tier medication that almost but not quite works, try augmenting with Abilify. Repeat Step 3. 7. Try electroconvulsive therapy. The end result might be the recommendation “try Lexapro!”, but you know where to go if that doesn’t work. A psychiatrist armed with this guideline can do much better work than one who just happens to know that Lexapro is the best antidepressant, even if Lexapro really is the best antidepressant. Whenever I’m hopelessly confused about what to do with a difficult patient, I find it really reassuring that I can go back to a guideline like this, put together by top psychiatrists working off the best evidence available. This makes it even more infuriating that there’s nothing like this for other areas I care about.