The risk or severity of adverse effects can be increased when Indiplon is combined with Cetirizine. The risk or severity of adverse effects can be increased when Zuclopenthixol is combined with Cetirizine. The risk or severity of adverse effects can be increased when Trans-2-Phenylcyclopropylamine is combined with Cetirizine. Nabilone may increase the central nervous system depressant (CNS depressant) activities of Cetirizine. The risk or severity of adverse effects can be increased when Agomelatine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Levobupivacaine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Sevoflurane is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Zonisamide. The risk or severity of adverse effects can be increased when Cetirizine is combined with Ziconotide. The risk or severity of adverse effects can be increased when Zaleplon is combined with Cetirizine. The risk or severity of adverse effects can be increased when Diphenoxylate is combined with Cetirizine. The risk or severity of adverse effects can be increased when Canertinib is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Fluticasone propionate. The risk or severity of adverse effects can be increased when Tetracaine is combined with Cetirizine. Pseudoephedrine may decrease the sedative activities of Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Alaproclate. The risk or severity of adverse effects can be increased when Alprazolam is combined with Cetirizine. The risk or severity of adverse effects can be increased when Barbital is combined with Cetirizine. The risk or severity of adverse effects can be increased when Ethchlorvynol is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Paroxetine. The risk or severity of adverse effects can be increased when Gamma Hydroxybutyric Acid is combined with Cetirizine. 2,5-Dimethoxy-4-ethylamphetamine may decrease the sedative activities of Cetirizine. The risk or severity of adverse effects can be increased when Butabarbital is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Sertraline. The risk or severity of adverse effects can be increased when Loxapine is combined with Cetirizine. 4-Bromo-2,5-dimethoxyamphetamine may decrease the sedative activities of Cetirizine. Chlorphentermine may decrease the sedative activities of Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Fexofenadine. The risk or severity of adverse effects can be increased when Ethylmorphine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Nitrazepam is combined with Cetirizine. The risk or severity of adverse effects can be increased when Quazepam is combined with Cetirizine. The risk or severity of adverse effects can be increased when Chloroprocaine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Vigabatrin. The risk or severity of adverse effects can be increased when Melperone is combined with Cetirizine. The risk or severity of adverse effects can be increased when Pimozide is combined with Cetirizine. The risk or severity of adverse effects can be increased when Perphenazine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Dexmedetomidine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Dihydroetorphine is combined with Cetirizine. The therapeutic efficacy of Hyaluronidase can be decreased when used in combination with Cetirizine. The risk or severity of adverse effects can be increased when Quetiapine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Nefazodone. The risk or severity of adverse effects can be increased when Cetirizine is combined with Venlafaxine. The risk or severity of adverse effects can be increased when Phenytoin is combined with Cetirizine. The risk or severity of adverse effects can be increased when Fludiazepam is combined with Cetirizine. The risk or severity of adverse effects can be increased when Acepromazine is combined with Cetirizine. Cetirizine may increase the sedative activities of Ropinirole. The risk or severity of adverse effects can be increased when Oxazepam is combined with Cetirizine. The risk or severity of adverse effects can be increased when Bromperidol is combined with Cetirizine. The risk or severity of adverse effects can be increased when Diphenhydramine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Nitrous oxide is combined with Cetirizine. The risk or severity of adverse effects can be increased when Thiopental is combined with Cetirizine. Dextroamphetamine may decrease the sedative activities of Cetirizine. The risk or severity of adverse effects can be increased when Pethidine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Aripiprazole is combined with Cetirizine. The risk or severity of adverse effects can be increased when Fluvoxamine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Hydromorphone is combined with Cetirizine. The risk or severity of adverse effects can be increased when Methylphenobarbital is combined with Cetirizine. The risk or severity of adverse effects can be increased when Etizolam is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Clonidine. The risk or severity of adverse effects can be increased when Osanetant is combined with Cetirizine. The risk or severity of adverse effects can be increased when Molindone is combined with Cetirizine. Brimonidine may increase the central nervous system depressant (CNS depressant) activities of Cetirizine. The risk or severity of adverse effects can be increased when Mesoridazine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Butamben is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Pomalidomide. The risk or severity of adverse effects can be increased when Ziprasidone is combined with Cetirizine. The risk or severity of adverse effects can be increased when Alfentanil is combined with Cetirizine. Perampanel may increase the central nervous system depressant (CNS depressant) activities of Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Scopolamine. The risk or severity of adverse effects can be increased when Thiothixene is combined with Cetirizine. The risk or severity of adverse effects can be increased when Bromazepam is combined with Cetirizine. The risk or severity of adverse effects can be increased when Melatonin is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Metaxalone. The risk or severity of adverse effects can be increased when Chlordiazepoxide is combined with Cetirizine. Cetirizine may increase the central nervous system depressant (CNS depressant) activities of Orphenadrine. The risk or severity of adverse effects can be increased when Etorphine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Morphine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Sulpiride is combined with Cetirizine. The risk or severity of adverse effects can be increased when Lorazepam is combined with Cetirizine. The risk or severity of adverse effects can be increased when Alphaprodine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Pizotifen. The risk or severity of adverse effects can be increased when Cetirizine is combined with Clonazepam. The risk or severity of adverse effects can be increased when Amitriptyline is combined with Cetirizine. The risk or severity of adverse effects can be increased when Sertindole is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Nortriptyline. The risk or severity of adverse effects can be increased when Butalbital is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Levocetirizine. The risk or severity of adverse effects can be increased when Piritramide is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Loratadine. The risk or severity of adverse effects can be increased when Dextromoramide is combined with Cetirizine. The risk or severity of adverse effects can be increased when Methoxyflurane is combined with Cetirizine. The risk or severity of adverse effects can be increased when Lidocaine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Methapyrilene is combined with Cetirizine. Cetirizine may increase the central nervous system depressant (CNS depressant) activities of Ethanol. Benzphetamine may decrease the sedative activities of Cetirizine. The risk or severity of adverse effects can be increased when Amisulpride is combined with Cetirizine. The risk or severity of adverse effects can be increased when Chlorpromazine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Etidocaine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Gepirone is combined with Cetirizine. The risk or severity of adverse effects can be increased when Desflurane is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Clobazam. The risk or severity of adverse effects can be increased when Haloperidol is combined with Cetirizine. The risk or severity of adverse effects can be increased when Articaine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Perospirone is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Ramelteon. The risk or severity of adverse effects can be increased when Flurazepam is combined with Cetirizine. The risk or severity of adverse effects can be increased when Thiamylal is combined with Cetirizine. Tapentadol may increase the central nervous system depressant (CNS depressant) activities of Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Citalopram. Cetirizine may increase the central nervous system depressant (CNS depressant) activities of Methotrimeprazine. The risk or severity of adverse effects can be increased when Ketobemidone is combined with Cetirizine. The risk or severity of adverse effects can be increased when Oxymorphone is combined with Cetirizine. The risk or severity of adverse effects can be increased when Dezocine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Temazepam is combined with Cetirizine. The risk or severity of adverse effects can be increased when Topiramate is combined with Cetirizine. The risk or severity of adverse effects can be increased when Dapiprazole is combined with Cetirizine. The risk or severity of adverse effects can be increased when Methaqualone is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Pipotiazine. The risk or severity of adverse effects can be increased when Ecopipam is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Tizanidine. The risk or severity of adverse effects can be increased when Secobarbital is combined with Cetirizine. The risk or severity of adverse effects can be increased when Propofol is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cyclobenzaprine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Triflupromazine is combined with Cetirizine. The risk or severity of adverse effects can be increased when Alfaxalone is combined with Cetirizine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Triprolidine. The risk or severity of adverse effects can be increased when Cetirizine is combined with Levomilnacipran. The risk or severity of adverse effects can be increased when Enflurane is combined with Cetirizine. The risk or severity of adverse effects can be increased when Ethyl loflazepate is combined with Cetirizine.