Plague doctor

Blending spellcasting with science, you distill your
 magic into concoctions that harm or heal. Plague Doctors
 often wear grotesque masks protecting them from toxic
 ingredients. Many regard the mask with fear as a sign of
 pestilence, making Plague Doctors a source of both hope
 and trepidation.

Potion Craft

Beginning when you select this arcane tradition at
 2nd level, you gain proficiency in Medicine and with
 alchemist’s supplies and herbalism kits.
 Additionally, you have learned to create magical
 concoctions. You can create any number of concoctions
 using your alchemist supplies or herbalism kit for 10
 minutes, expending a spell slot for each concoction created.
 When you do, for each concoction created, choose a
 spell from your wizard’s spell book that targets only one
 creature. The chosen spell must be of an equal or lower
 level than the expended spell slot.
 When a creature consumes the concoction, it becomes
 the target of the spell as if you had just cast it. If the spell
 requires concentration, the creature that consumes the
 potion needs to concentrate on it. Concoctions created
 this way lose their magical effect at the end of your next
 long rest.

Good Medicine

Also at 2nd level, when you craft a concoction, you
 can choose to expend a spell slot without choosing a
 spell, instead creating good medicine. When a creature
 consumes your good medicine, you roll 1d8 per level of
 the spell slot expended casting the spell, and the creature
 regains an equal number of hit points. If you expended a
 spell slot of 3rd level or higher, you also end all diseases
 afflicting the creature.

Bad Medicine

Starting at 6th level, when you craft a concoction you
 can choose to expend a spell slot without choosing a
 spell, instead crafting bad medicine. When you create
 a dose of bad medicine, choose one effect per level of
 spell slot expended.
• The creature is poisoned.
• The creature’s movement speeds are halved.
• The creature takes an additional 1d4 necrotic damage
 the first time it takes damage each turn.
• The creature takes 1d6 poison damage each time it
 takes an action, bonus action, or reaction on a turn.
• The creature takes acid damage equal to the level of
 the spell slot expended at the start of each of its turns.
As an action, you can hurl a dose of bad medicine
 at a point you can see within 30 feet. Creatures within
 10 feet of that point must make a Constitution saving
 throw against your wizard spell save DC. On a failure,
 the creature suffers all of the chosen effects for the
 next minute.
 As an action, the affected creature can attempt another
 Constitution saving throw to end any effects early.

Breathe It In

Beginning at 10th level, being persistently exposed to the
 most deadly ailments known has given you some small
 measure of resistance to them. After you take necrotic or
 poison damage, you gain temporary hit points equal to
 the damage. In addition, you are immune to disease and
 have advantage on saving throws against being poisoned.

Medicinal Master

Starting at 14th level, when you heal with your Good
 Medicine or deal damage with your Bad Medicine, roll
 an additional 2d8 to determine the amount of hit points
 regained or necrotic damage dealt.