The following drugs will decrease phenytoin effect

#	enzyme	inducers
0	2C9	carbamazepine
1	2C19	carbamazepine
2	2C9	dabrafenib
3	2C9	enzalutamide
4	2C19	efavirenz
5	2C19	enzalutamide
6	2C19	letermovir
7	2C9	letermovir
8	2C19	norethindrone
9	2C19	prednisone
10	2C9	nevirapine
11	2C9	phenobarbital
12	2C19	rifampicin
13	2C19	ritonavir
14	2C9	rifampin
15	2C9	secobarbital

the follwing drugs will Increase phenytoin effect

#	enzyme	Inhibitors	level
0	2C9	amiodarone	Moderate inhibitor
1	2C19	armodafinil	Weak inhibitor
2	2C9	capecitabine	Weak inhibitor
3	2C9	ceritinib	Weak inhibitor
4	2C19	chloramphenicol	In-Vitro Only
5	2C19	cimetidine	Weak inhibitor
6	2C19	citalopram	Weak inhibitor
7	2C9	efavirenz	Weak inhibitor
8	2C19	esomeprazole	Weak inhibitor
9	2C19	felbamate	Weak inhibitor
10	2C9	fenofibrate	In-Vitro Only
11	2C9	fluconazole	Moderate inhibitor
12	2C19	fluconazole	Moderate inhibitor
13	2C19	fluoxetine	Moderate inhibitor
14	2C9	fluvastatin	In-Vitro Only
15	2C9	fluvoxamine	In-Vitro Only
16	2C19	fluvoxamine	Strong inhibitor
17	2C9	isoniazid	Weak inhibitor
18	2C19	isoniazid	Weak inhibitor
19	2C19	ketoconazole	Moderate inhibitor
20	2C19	luliconazole	Weak inhibitor
21	2C9	metronidazole	Moderate inhibitor
22	2C19	modafinil	Weak inhibitor
23	2C19	omeprazole	Weak inhibitor
24	2C19	oral contraceptives	Weak inhibitor
25	2C19	oritavancin	In-Vitro Only
26	2C19	pantoprazole	Weak inhibitor
27	2C9	phenylbutazone	Moderate inhibitor
28	2C9	quercetin	Weak inhibitor
29	2C19	quercetin	In-Vitro Only
30	2C9	sulfamethoxazole	Weak inhibitor
31	2C9	sulfaphenazole	Strong inhibitor
32	2C19	ticlopidine	Strong inhibitor
33	2C19	topiramate	under review
34	2C9	voriconazole	Weak inhibitor
35	2C19	voriconazole	Moderate inhibitor
36	2C9	zafirlukast	Weak inhibitor

The following drugs will decreased effect by phenytoin effect

#	enzyme	drug
1	3A457	abemaciclib
2	3A457	abiraterone
3	3A457	acalabrutinib
4	3A457	alectinib
5	3A457	alfentanil
6	3A457	alprazolam
7	3A457	amitriptyline
8	3A457	amlodipine
9	3A457	apixaban
10	3A457	aprepitant
11	3A457	aripiprazole
12	2B6	artemisinin
13	3A457	astemizole
14	3A457	atorvastatin
15	3A457	avanafil
16	3A457	axitinib
17	3A457	boceprevir
18	3A457	bosutinib
19	3A457	brexpiprazole
20	3A457	brigatinib
21	2B6	bupropion
22	3A457	buspirone
23	3A457	cafergot
24	3A457	caffeine
25	3A457	carbamazepine
26	3A457	cariprazine
27	3A457	ceritinib
28	3A457	cerivastatin
29	3A457	chlorpheniramine
30	3A457	cilostazol
31	3A457	cisapride
32	3A457	citalopram
33	3A457	clarithromycin
34	2B6	clobazam
35	3A457	clobazam
36	3A457	clopidogrel
37	3A457	cobimetinib
38	3A457	cocaine
39	3A457	codeine
40	3A457	colchicine
41	3A457	copanlisib
42	3A457	crizotinib
43	2B6	cyclophosphamide
44	3A457	cyclosporine
45	3A457	dabrafenib
46	3A457	daclatasvir
47	3A457	dapsone
48	3A457	deflazacort
49	3A457	dexamethasone
50	3A457	dextromethorphan
51	3A457	diazepam
52	3A457	diltiazem
53	3A457	docetaxel
54	3A457	dolutegravir
55	3A457	domperidone
56	3A457	doxepin
57	2B6	efavirenz
58	3A457	elagolix
59	3A457	elbasvir/grazoprevir
60	3A457	eliglustat
61	3A457	enzalutamide
62	3A457	eplerenone
63	3A457	erythromycin2
64	3A457	escitalopram
65	3A457	esomeprazole
66	3A457	estradiol
67	3A457	felodipine
68	3A457	fentanyl
69	3A457	finasteride
70	3A457	flibanserin
71	3A457	gleevec
72	3A457	haloperidol
73	3A457	hydrocortisone
74	3A457	ibrutinib
75	3A457	idelalisib
76	2B6	ifosphamide
77	3A457	indacaterol
78	3A457	indinavir
79	3A457	irinotecan
80	3A457	isavuconazonium
81	3A457	ivabradine
82	3A457	ivacaftor
83	2B6	ketamine
84	3A457	LAAM
85	3A457	lansoprazole
86	3A457	lenvatinib
87	3A457	lercanidipine
88	3A457	lidocaine
89	3A457	linagliptin
90	3A457	lovastatin
91	3A457	macitentan
92	3A457	mavacamten
93	2B6	meperidine
94	2B6	methadone
95	3A457	methadone
96	3A457	midazolam
97	3A457	naldemedine
98	3A457	naloxegol
99	3A457	nateglinide
100	3A457	nelfinavir
101	3A457	neratinib
102	3A457	netupitant/palonosetron
103	2B6	nevirapine
104	3A457	nevirapine
105	3A457	nifedipine
106	3A457	nirmatrelvir
107	3A457	nisoldipine
108	3A457	nitrendipine
109	3A457	olaparib
110	3A457	omeprazole
111	3A457	ondansetron
112	3A457	osimertinib
113	3A457	ospemifene
114	3A457	palbociclib
115	3A457	panobinostat
116	3A457	pantoprazole
117	3A457	perampanel
118	3A457	pimavanserin
119	3A457	pimozide
120	3A457	pomalidomide
121	3A457	ponatinib
122	3A457	progesterone
123	2B6	propafol
124	3A457	propranolol
125	3A457	quetiapine
126	3A457	quinidine
127	3A457	quinine
128	3A457	regorafenib
129	3A457	ribociclib
130	3A457	rilpivirine
131	3A457	risperidone
132	3A457	ritonavir
133	3A457	rivaroxaban
134	3A457	roflumilast
135	3A457	rolapitant
136	3A457	romidepsin
137	3A457	rucaparib
138	3A457	ruxolitinib
139	3A457	salmeterol
140	3A457	saquinavir
141	2B6	selegiline
142	3A457	selexipag
143	3A457	sildenafil
144	3A457	simeprevir
145	3A457	simvastatin
146	3A457	sirolimus
147	3A457	sonidegib
148	2B6	sorafenib
149	3A457	sorafenib
150	3A457	sunitinib
151	3A457	suvorexant
152	3A457	tacrolimus(fk506)
153	3A457	tamoxifen
154	3A457	tasimelteon
155	3A457	taxol
156	3A457	telaprevir
157	3A457	telithromycin
158	3A457	terfenadine
159	3A457	testosterone
160	3A457	ticagrelor
161	3A457	tofacitinib
162	3A457	tolvaptan
163	3A457	torisel
164	2B6	tramadol
165	3A457	tramadol
166	3A457	trazodone
167	3A457	valbenazine
168	3A457	vandetanib
169	2B6	velpatasvir
170	3A457	velpatasvir
171	3A457	vemurafenib
172	3A457	venetoclax
173	3A457	venlafaxine
174	3A457	verapamil
175	3A457	vilazodone
176	3A457	vincristine
177	3A457	vorapaxar
178	3A457	voriconazole
179	3A457	zaleplon
180	3A457	ziprasidone
181	3A457	zolpidem

will decrease phenytoin effect

#

enzyme

inducers

phenytoin will not affect

Strong inhibitor is one that causes a ≥ 5-fold decrease in the plasma AUC values or more than 80% decrease in clearance.
Moderate inhibitor is one that causes a 2 fold to < 5-fold decrease in the plasma AUC values or 50-80% decrease in clearance.
Weak inhibitor is one that causes a ≥ 1.25-fold but < 2-fold decrease in the plasma AUC values or 20-50% decrease in clearance.
In-Vitro Only In-Vitro Only Inhibitor strength.
under review Inhibitor strength level is under review.