In Fallout 4, chems have a variety of uses. For example, some chems give you a greater damage threshold in combat, while others may increase intelligence for a short duration. If you use a chem too often it may lead to addiction, so be careful. Additionally, all chems can be crafted at a crafting station, so if you have the right materials there is no need to waste your money and purchase them. Chems can also be stacked, with no limit. This means you can take as many chems as you want, so go crazy!
Regular Chem’s and Their Effects
Alcohol
If you consume alcohol both your charisma and strength will be increased. However, your intelligence will go down. Stronger alcohols such as moonshine have a stronger effect.
Jet
When you take Jet, time slows down for ten seconds. This is great for combat situations, especially fast enemies that may be upon you in a second. A word of warning: it is the easiest drug to get addicted to in game.
Buffout
Once used, Buffout increases plus two points in both Strength and Endurance, as well as increasing your max AP by 50. Buffout is great for when you’re over encumbered and need to fast travel.
Med X
Med-X raises your damage resistance by 25 points. This is great for when you are about to head into a big fight, as it’ll give you a little extra wiggle room to survive.
Psycho
Psycho is phenomenal for combat, as it increases both your damage and damage resistance by 25%.
Mentats
Using mentats gives you a boost of two towards your intelligence and perception. That’s great if you want to use V.A.T.S. Additionally, you’ll get more XP if you use mentats right before finishing up a quest.
Advanced Chem’s and Their Effects
Berry Mentats
Berry mentats will give your intelligence an extra five point boost and also highlight living targets for a total of eight minutes. This is great for a stealth build, as you’ll most likely be active at night. To craft Berry Mentats you will need an anti freeze bottle, Mentats, and Tarberry x 2.
Grape Mentats
Once taken, Grape Mentats will give you a 10% boost to bartering and five more points in Charisma. To craft them, you will need Hubflower x 2, Mentats, and Whiskey.
Orange Mentats
Orange mentats are great for snipers, as once taken they will increase Perception by five points and give you increased VATS accuracy for eight minutes. To craft them, you will need Asbestos, Carrot x 3, and Mentats.
Bufftats
Bufftats will give you the best of both worlds. You’ll gain plus 65 max health and increased Strength and Endurance by three from the Buffout, in addition to the plus three to perception of the Mentats. To craft Bufftats, you will need one buffout and one mentat.
Buffjet
Buffjet is a beast of a drug, giving you +3 strength, +3 endurance, +65 max health, +35 max AP, and time slows down. To craft it, you’ll need one Buffout and one Jet.
Psycho Jet
Psycho Jet gives you a 25% boost to damage, 35 extra damage resistance, plus 40 max AP, and time slows down for 15 seconds. You will need one Jet and one Psycho to craft it.
Ultra Jet
Ultra Jet is perfect for the VATS enthusiast. It will slow time for fifteen seconds and give you 100 more points of AP. To craft, you will require bloodleaf, fertilizer, Jet, and plastic x 2.
Psychobuff
Once taken, Psychobuff will give you +25% damage, +3 strength, +3 endurance, and +65 max health. You will need one Buffout and one Psycho to craft.
Day tripper
Day tripper is very rare, and you are unable to craft it. If used, it will give you a plus three boost to charisma and luck, at the cost of minus two to strength.
Overdrive
Overdrive will increase your damage and critical chance by 25%. You will need Acid x 2, Nuka Cola, and Psycho to craft.
Jetfuel
Jetfuel will increase your maximum AP by 35, in addition to making it regenerate faster than before. This is great for VATS users. You will need flamer fuel and Jet to craft it.
X-Cell
X-Cell is extremely rare and highly addictive. The addiction rate is 50%. X-Cell gives a plus two bonus to all stats.
Daddy-O
Daddy-O cannot be crafted. Once ingested, it gives a +3 boost to intelligence and perception, but impacts charisma with a minus 2.
Fury
Fury is great for melee players. With Fury, your melee damage is increased by 50%, and your damage resistance is boosted by 25%. Additionally, perception is boosted by 5. To craft it, you will need a berserk syringe and Buffout.
Chem Addiction
If you take too many chems, you will become addicted to them. This means, depending on what chem(s) you are addicted to, penalties to your stats will happen, like minus one to perception or strength. You can check to see how you are affected by visiting the STATUS page of your Pip Boy and pressing the “show effects” button.
To cure your addiction(s), you have a few options. If you do not take the substance(s) you are addicted to for several in game days, then eventually you will recover. Alternatively, you can go to a doctor, who for a price (of course) will cure you. Or, if you have gotten your hands on Addictol, you can use that to cure your addiction(s) instantly. If you have a radscorpion egg, you can craft a radscorpion egg omelet, which will also instantly get rid of any addiction(s).