The risk or severity of adverse effects can be increased when Dihydrocodeine is combined with Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Adipiplon. The risk or severity of adverse effects can be increased when Dapiprazole is combined with Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Imipramine. The risk or severity of adverse effects can be increased when Trazodone is combined with Metoclopramide. The metabolism of Trazodone can be decreased when combined with Fluconazole. The risk or severity of adverse effects can be increased when Trazodone is combined with Gepirone. The risk or severity of adverse effects can be increased when Trazodone is combined with Pipotiazine. The risk or severity of adverse effects can be increased when Trazodone is combined with Tranylcypromine. The serum concentration of Trazodone can be increased when it is combined with Abiraterone. Brimonidine may increase the central nervous system depressant (CNS depressant) activities of Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Doxepin. The metabolism of Trazodone can be decreased when combined with Amiodarone. Trazodone may increase the QTc-prolonging activities of Moxifloxacin. The risk or severity of adverse effects can be increased when Trazodone is combined with Nortriptyline. Trazodone may increase the sedative activities of Pramipexole. The serum concentration of Trazodone can be decreased when it is combined with Deferasirox. The risk or severity of adverse effects can be increased when Trazodone is combined with Hexobarbital. The risk or severity of adverse effects can be increased when Trazodone is combined with Ergonovine. Trazodone may increase the QTc-prolonging activities of Ibutilide. The risk or severity of adverse effects can be increased when Trazodone is combined with Fospropofol. The risk or severity of adverse effects can be increased when Trazodone is combined with Efavirenz. The risk or severity of adverse effects can be increased when Trazodone is combined with Ethosuximide. The risk or severity of adverse effects can be increased when Trazodone is combined with Zonisamide. The risk or severity of adverse effects can be increased when Trazodone is combined with Dimenhydrinate. The risk or severity of adverse effects can be increased when Butorphanol is combined with Trazodone. Phenoxypropazine may increase the serotonergic activities of Trazodone. Zimelidine may increase the serotonergic activities of Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Flunarizine. The risk or severity of adverse effects can be increased when Trazodone is combined with Baclofen. The serum concentration of Vincristine can be decreased when it is combined with Trazodone. The serum concentration of Trazodone can be decreased when it is combined with St. John's Wort. The risk or severity of adverse effects can be increased when Trazodone is combined with Amisulpride. The risk or severity of adverse effects can be increased when Trazodone is combined with Flibanserin. Trazodone may increase the central nervous system depressant (CNS depressant) activities of Mirtazapine. The risk or severity of adverse effects can be increased when Trazodone is combined with Dexbrompheniramine. Trazodone may increase the QTc-prolonging activities of Anagrelide. The risk or severity of adverse effects can be increased when Dextropropoxyphene is combined with Trazodone. The serum concentration of Trazodone can be increased when it is combined with Cobicistat. Trazodone may increase the QTc-prolonging activities of Citalopram. The risk or severity of adverse effects can be increased when Temazepam is combined with Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Thioproperazine. The risk or severity of adverse effects can be increased when Trazodone is combined with DPDPE. Indalpine may increase the serotonergic activities of Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Pethidine. Hydracarbazine may increase the serotonergic activities of Trazodone. The serum concentration of Ledipasvir can be decreased when it is combined with Trazodone. Toloxatone may increase the serotonergic activities of Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Dextromoramide. The metabolism of Tacrolimus can be decreased when combined with Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Opium. Trazodone may increase the sedative activities of Rotigotine. The risk or severity of adverse effects can be increased when Trazodone is combined with Melperone. The risk or severity of adverse effects can be increased when Trazodone is combined with Drotebanol. The risk or severity of adverse effects can be increased when Trazodone is combined with 7-Nitroindazole. The serum concentration of Trazodone can be decreased when it is combined with Tocilizumab. Trazodone may increase the QTc-prolonging activities of Zuclopenthixol. The risk or severity of adverse effects can be increased when Trazodone is combined with Protriptyline. The risk or severity of adverse effects can be increased when Trazodone is combined with Dihydroergotamine. The risk or severity of adverse effects can be increased when Trazodone is combined with Eltanolone. The risk or severity of adverse effects can be increased when Trazodone is combined with Cyamemazine. Hydroxyzine may increase the central nervous system depressant (CNS depressant) activities of Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Scopolamine. The risk or severity of adverse effects can be increased when Trazodone is combined with Tiapride. Venlafaxine may increase the serotonergic activities of Trazodone. The serum concentration of Trazodone can be increased when it is combined with Fosaprepitant. The risk or severity of adverse effects can be increased when Trazodone is combined with Guanfacine. Caroxazone may increase the serotonergic activities of Trazodone. The serum concentration of Trazodone can be decreased when it is combined with Siltuximab. The metabolism of Trazodone can be increased when combined with Rifapentine. Trazodone may decrease the anticoagulant activities of Warfarin. The risk or severity of adverse effects can be increased when Trazodone is combined with Sumatriptan. Trazodone may increase the QTc-prolonging activities of Flecainide. The risk or severity of adverse effects can be increased when Trazodone is combined with Bromocriptine. The risk or severity of adverse effects can be increased when Trazodone is combined with Aceprometazine. The risk or severity of adverse effects can be increased when Trazodone is combined with Sepranolone. The metabolism of Trazodone can be decreased when combined with Diphenhydramine. The risk or severity of adverse effects can be increased when Remifentanil is combined with Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Ethyl loflazepate. The metabolism of Trazodone can be increased when combined with Primidone. The risk or severity of adverse effects can be increased when Trazodone is combined with Amoxapine. The risk or severity of adverse effects can be increased when Enflurane is combined with Trazodone. The metabolism of Trazodone can be increased when combined with Rifabutin. Iproniazid may increase the serotonergic activities of Trazodone. The metabolism of Trazodone can be decreased when combined with Idelalisib. Etoperidone may increase the serotonergic activities of Trazodone. The metabolism of Trazodone can be decreased when combined with Sildenafil. L-Tryptophan may increase the serotonergic activities of Trazodone. Alaproclate may increase the serotonergic activities of Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Procarbazine. The metabolism of Trazodone can be decreased when combined with Imatinib. Trazodone may increase the QTc-prolonging activities of Ciprofloxacin. The risk or severity of adverse effects can be increased when Trazodone is combined with Glutethimide. The risk or severity of adverse effects can be increased when Secobarbital is combined with Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Norflurane. The metabolism of Trazodone can be increased when combined with Pentobarbital. The risk or severity of adverse effects can be increased when Trazodone is combined with Etizolam. The serum concentration of Conivaptan can be increased when it is combined with Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Heroin. The risk or severity of adverse effects can be increased when Trazodone is combined with Pizotifen. The risk or severity of adverse effects can be increased when Trazodone is combined with Vortioxetine. The risk or severity of adverse effects can be increased when Trazodone is combined with Triprolidine. The risk or severity of adverse effects can be increased when Trazodone is combined with Ethyl chloride. The risk or severity of adverse effects can be increased when Levorphanol is combined with Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Flunitrazepam. The risk or severity of adverse effects can be increased when Hydromorphone is combined with Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Almotriptan. The risk or severity of adverse effects can be increased when Trazodone is combined with Halazepam. Tropisetron may increase the serotonergic activities of Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Levetiracetam. The serum concentration of Trazodone can be decreased when it is combined with Dabrafenib. The metabolism of Trazodone can be decreased when combined with Dosulepin. The serum concentration of Trazodone can be increased when it is combined with Telaprevir. The serum concentration of Trazodone can be increased when it is combined with Luliconazole. Trazodone may increase the QTc-prolonging activities of Levofloxacin. The risk or severity of adverse effects can be increased when Trazodone is combined with Brexpiprazole. The serum concentration of Trazodone can be decreased when it is combined with Fosphenytoin. The risk or severity of adverse effects can be increased when Aripiprazole is combined with Trazodone. The serum concentration of Linagliptin can be decreased when it is combined with Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Etidocaine. The risk or severity of adverse effects can be increased when Trazodone is combined with Prilocaine. The risk or severity of adverse effects can be increased when Sevoflurane is combined with Trazodone. The risk or severity of adverse effects can be increased when Trazodone is combined with Desipramine. Sodium oxybate may increase the central nervous system depressant (CNS depressant) activities of Trazodone. Trazodone may increase the QTc-prolonging activities of Ziprasidone. The risk or severity of adverse effects can be increased when Trazodone is combined with Eletriptan. Trazodone may increase the QTc-prolonging activities of Gemifloxacin. Trazodone may increase the QTc-prolonging activities of Ofloxacin. The risk or severity of adverse effects can be increased when Trazodone is combined with Zolmitriptan. The risk or severity of adverse effects can be increased when Trazodone is combined with Methoxyflurane.