Details of Drug Interaction | MecDDI

Drug General Information (ID: DDISCN96EH)
Drug Name			Olanzapine		Drug Info		Guanethidine		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antipsychotic Agents				Antihypertensive Agents
Structure

Mechanism of Olanzapine-Guanethidine Interaction (Severity Level: Moderate)
Additive hypotensive effects Click to Show/Hide Mechanism Graph

Drug Name		Olanzapine				Guanethidine
Mechanism		Hypotensive effects Dopamine D2 receptor Agonist				Antihypertensive agent Noradrenaline transporter Inducer
Key Mechanism Factor 1
		Factor Name		Dopamine D2 receptor				× Structure Sequence MDPLNLSWYDDDLERQNWSRPFNGSDGKADRPHYNYYATLLTLLIAVIVFGNVLVCMAVSREKALQTTTNYLIVSLAVADLLVATLVMPWVVYLEVVGEWKFSRIHCDIFVTLDVMMCTASILNLCAISIDRYTAVAMPMLYNTRYSSKRRVTVMISIVWVLSFTISCPLLFGLNNADQNECIIANPAFVVYSSIVSFYVPFIVTLLVYIKIYIVLRRRRKRVNTKRSSRAFRAHLRAPLKGNCTHPEDMKLCTVIMKSNGSFPVNRRRVEAARRAQELEMEMLSSTSPPERTRYSPIPPSHHQLTLPDPSHHGLHSTPDSPAKPEKNGHAKDHPKIAKIFEIQTMPNGKTRTSLKTMSRRKLSQQKEKKATQMLAIVLGVFIICWLPFFITHILNIHCDCNIPPVLYSAFTWLGYVNSAVNPIIYTTFNIEFRKAFLKILHC
		Gene Name		DRD2
		Uniprot ID		DRD2_HUMAN
		KEGG Pathway		hsa:1813
		Protein Family		G-protein coupled receptor 1 family
		Protein Function		Dopamine receptor whose activity is mediated by G proteins which inhibit adenylyl cyclase (PubMed:21645528). Positively regulates postnatal regression of retinal hyaloid vessels via suppression of VEGFR2/KDR activity, downstream of OPN5 (By similarity). Click to Show/Hide
Key Mechanism Factor 2
		Factor Name		Norepinephrine transporter				× Structure Sequence MLLARMNPQVQPENNGADTGPEQPLRARKTAELLVVKERNGVQCLLAPRDGDAQPRETWGKKIDFLLSVVGFAVDLANVWRFPYLCYKNGGGAFLIPYTLFLIIAGMPLFYMELALGQYNREGAATVWKICPFFKGVGYAVILIALYVGFYYNVIIAWSLYYLFSSFTLNLPWTDCGHTWNSPNCTDPKLLNGSVLGNHTKYSKYKFTPAAEFYERGVLHLHESSGIHDIGLPQWQLLLCLMVVVIVLYFSLWKGVKTSGKVVWITATLPYFVLFVLLVHGVTLPGASNGINAYLHIDFYRLKEATVWIDAATQIFFSLGAGFGVLIAFASYNKFDNNCYRDALLTSSINCITSFVSGFAIFSILGYMAHEHKVNIEDVATEGAGLVFILYPEAISTLSGSTFWAVVFFVMLLALGLDSSMGGMEAVITGLADDFQVLKRHRKLFTFGVTFSTFLLALFCITKGGIYVLTLLDTFAAGTSILFAVLMEAIGVSWFYGVDRFSNDIQQMMGFRPGLYWRLCWKFVSPAFLLFVVVVSIINFKPLTYDDYIFPPWANWVGWGIALSSMVLVPIYVIYKFLSTQGSLWERLAYGITPENEHHLVAQRDIRQFQLQHWLAI
		Gene Name		SLC6A2
		Uniprot ID		SC6A2_HUMAN
		KEGG Pathway		hsa:6530
		Protein Family		Sodium:neurotransmitter symporter (SNF) (TC 2.A.22) family
		Protein Function		Amine transporter. Terminates the action of noradrenaline by its high affinity sodium-dependent reuptake into presynaptic terminals. Click to Show/Hide
Mechanism Description		Additive hypotensive effects by the combination of Olanzapine and Guanethidine

Recommended Action
Management		Close clinical monitoring for development of hypotension is recommended if phenothiazines or neuroleptic agents are used in patients receiving antihypertensive medications or vasodilators. A lower starting dosage and slower titration of the phenothiazine or neuroleptic may be appropriate, especially in the elderly. Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia. Patients should also avoid driving or operating hazardous machinery.

References
1	Aronowitz JS, Chakos MH, Safferman AZ, Lieberman JA "Syncope associated with the combination of clozapine and enalapril." J Clin Psychopharmacol 14 (1994): 429-30. [PMID: 7884028]
2	Fruncillo R, Gibbons W, Vlasses P, Ferguson R "Severe hypotension associated with concurrent clonidine and antipsychotic medication." Am J Psychiatry 142 (1985): 274. [PMID: 2857531]
3	Markowitz JS, Wells BG, Carson WH "Interactions between antipsychotic and antihypertensive drugs." Ann Pharmacother 29 (1995): 603-9. [PMID: 7663034]
4	Product Information. Abilify (aripiprazole). Bristol-Myers Squibb, Princeton, NJ.
5	Product Information. Clozaril (clozapine). Novartis Pharmaceuticals, East Hanover, NJ.
6	Product Information. Geodon (ziprasidone). Pfizer US Pharmaceuticals, New York, NY.
7	Product Information. Rexulti (brexpiprazole). Otsuka American Pharmaceuticals Inc, Rockville, MD.
8	Product Information. Risperdal (risperidone). Janssen Pharmaceutica, Titusville, NJ.
9	Product Information. Seroquel (quetiapine). Zeneca Pharmaceuticals, Wilmington, DE.
10	Product Information. Zyprexa (olanzapine). Lilly, Eli and Company, Indianapolis, IN.
11	White WB "Hypotension with postural syncope secondary to the combination of chlorpromazine and captopril." Arch Intern Med 146 (1986): 1833-4. [PMID: 3530167]