Diphenhydramine

Diphenhydramine Brand Names

Aid to Sleep | Alka-Seltzer Plus Allergy | Aller-G-Time | Altaryl | Banophen | Benadryl | Benadryl Allergy | Benadryl Allergy Children’s | Benadryl Allergy Dye Free | Benadryl Allergy Kapgel | Benadryl Allergy Quick Dissolve | Benadryl Allergy Ultratab | Benadryl Children’s Allergy | Benadryl Children’s Allergy Fastmelt | Benadryl Children’s Perfect Measure | Benadryl Itch Stopping | Ben-Tann | Buckley’s Bedtime | Compoz Nighttime Sleep Aid | Dermarest Insect Bite | Dermarest Plus | Diphedryl | DIPHEN | Diphen AF | Diphenhist | DiphenMax | Dytan | ElixSure Allergy | Euthenicx | Genahist | Geri-Dryl | Hydramine | Itch Relief | M-Dryl | Nighttime Sleep Aid | Nytol | PediaCare Children’s Allergy | PediaCare Nighttime Cough | PediaClear Children’s Cough | PHARBEDRYL | Q-Dryl | Quenalin | Siladryl Allergy | Silphen | Simply Sleep | Sleep Tabs | Sleepinal | Sominex | Theraflu Multi-Symptom Strip | Triaminic Allergy Thin Strip | Triaminic Cough and Runny Nose Strip | Tusstat | Unisom | Uni-Tann | Valu-Dryl | Vanamine PD | Vicks Qlearquil Nighttime Allergy Relief | Vicks ZzzQuil Nightime Sleep-Aid

What is Diphenhydramine

Diphenhydramine is an oral, topical, and parenteral first generation, sedating antihistamine (H1-blocker) of the ethanolamine class.

Ethanolamine class antihistamines have significant antimuscarinic activity and produce marked sedation in most patients.

Diphenhydramine is often employed systemically to treat symptoms associated with allergic reactions, and in pre-medication regimens prior to use of medications or treatments associated with infusion-related reactions.

Oral formulations are often used to treat minor allergic reactions, seasonal allergies, and for some symptoms associated with the common cold. Because of its anticholinergic properties, diphenhydramine is effective in the relief of nausea, vomiting, and vertigo associated with motion sickness.

Due to its ability to induce drowsiness, it is also promoted as a non-prescription (OTC) treatment for sleep.

Diphenhydramine is also used to treat drug-induced extrapyramidal symptoms as well as to treat mild symptoms of Parkinson’s disease. Topical formulas are used to relieve pain and itching associated with insect bites, minor burns or cuts, skin irritations or rashes such as poison ivy, oak or sumac.

Diphenhydramine was originally approved by the FDA in 1946 as a prescription-only drug, but the oral and topical formulations were later changed to non-prescription (OTC) status.

Indications

1. allergic rhinitis
2. common cold
3. contact dermatitis
4. cough
5. drug-induced extrapyramidal symptoms
6. insect bites or stings
7. insomnia
8. motion sickness
9. nystagmus
10. Parkinson’s disease
11. parkinsonism
12. pruritus
13. Rhus dermatitis
14. urticaria
15. vertigo

For the treatment of urticaria, pruritus, or supportive treatment of allergic reactions; also for treating symptoms (e.g., rhinorrhea, sneezing) associated with allergic rhinitis or the common cold, and for cough caused by minor throat and bronchial irritation

for prevention and treatment of allergic rhinitis, urticaria, pruritus, or allergic reactions under prescription of a healthcare professional

Side Effects

1. abdominal pain
2. agranulocytosis
3. anaphylactic shock
4. appetite stimulation
5. asthenia
6. atopic dermatitis
7. blurred vision
8. chills
9. confusion
10. constipation
11. contact dermatitis
12. diarrhea
13. diplopia
14. dizziness
15. drowsiness
16. dysarthria
17. euphoria
18. fatigue
19. headache
20. hemolytic anemia
21. hyperhidrosis
22. increased urinary frequency
23. insomnia
24. irritability
25. mydriasis
26. nasal congestion
27. neuritis
28. paresthesias
29. photosensitivity
30. rash
31. restlessness
32. seizures
33. thrombocytopenia
34. tinnitus
35. urinary retention
36. urticaria
37. vertigo
38. weakness
39. weight gain
40. wheezing
41. xerophthalmia
42. xerostomia

Monitoring Parameters

• laboratory monitoring not necessary

Contraindications

• accidental exposure
• anticholinergic medications
• asthma
• bladder obstruction
• breast-feeding
• cardiac disease
• children
• chronic obstructive pulmonary disease (COPD)
• closed-angle glaucoma
• contact lenses
• driving or operating machinery
• geriatric
• GI obstruction
• hepatic disease
• hypertension
• ileus
• increased intraocular pressure
• infants
• neonates
• ocular exposure
• potential for overdose or poisoning
• pregnancy
• prostatic hypertrophy
• urinary retention

Interactions

• Acarbose
• Acebutolol
• Acetaminophen; Aspirin, ASA; Caffeine
• Acetaminophen; Butalbital
• Acetaminophen; Butalbital; Caffeine
• Acetaminophen; Butalbital; Caffeine; Codeine
• Acetaminophen; Caffeine
• Acetaminophen; Caffeine; Dihydrocodeine
• Acetaminophen; Caffeine; Magnesium Salicylate; Phenyltoloxamine
• Acetaminophen; Caffeine; Phenyltoloxamine; Salicylamide
• Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine
• Acetaminophen; Codeine
• Acetaminophen; Dextromethorphan; Pseudoephedrine
• Acetaminophen; Dichloralphenazone; Isometheptene
• Acetaminophen; Hydrocodone
• Acetaminophen; Oxycodone
• Acetaminophen; Pentazocine
• Acetaminophen; Propoxyphene
• Acetaminophen; Pseudoephedrine
• Acetaminophen; Tramadol
• Aclidinium; Formoterol
• Acrivastine; Pseudoephedrine
• Albiglutide
• Albuterol
• Albuterol; Ipratropium
• Aldesleukin, IL-2
• Alfentanil
• Aliskiren; Amlodipine
• Aliskiren; Amlodipine; Hydrochlorothiazide, HCTZ
• Aliskiren; Hydrochlorothiazide, HCTZ
• Alogliptin; Metformin
• Alogliptin; Pioglitazone
• Alosetron
• Alpha-blockers
• Alpha-glucosidase Inhibitors
• Alprazolam
• Amantadine
• Ambenonium Chloride
• Ambrisentan
• Amikacin
• Amiloride
• Amiloride; Hydrochlorothiazide, HCTZ
• Aminoglycosides
• Amiodarone
• Amitriptyline; Chlordiazepoxide
• Amlodipine
• Amlodipine; Atorvastatin
• Amlodipine; Benazepril
• Amlodipine; Celecoxib
• Amlodipine; Hydrochlorothiazide, HCTZ; Olmesartan
• Amlodipine; Hydrochlorothiazide, HCTZ; Valsartan
• Amlodipine; Olmesartan
• Amlodipine; Telmisartan
• Amlodipine; Valsartan
• Amobarbital
• Amoxapine
• Amphetamine
• Amphetamine; Dextroamphetamine
• Amphetamine; Dextroamphetamine Salts
• Angiotensin II receptor antagonists
• Angiotensin-converting enzyme inhibitors
• Anticholinergics
• Apomorphine
• Apraclonidine
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• Arformoterol
• Artemether; Lumefantrine
• Articaine; Epinephrine
• Asenapine
• Aspirin, ASA; Butalbital; Caffeine
• Aspirin, ASA; Butalbital; Caffeine; Codeine
• Aspirin, ASA; Caffeine; Dihydrocodeine
• Aspirin, ASA; Caffeine; Orphenadrine
• Aspirin, ASA; Carisoprodol
• Aspirin, ASA; Carisoprodol; Codeine
• Aspirin, ASA; Oxycodone
• Atazanavir; Cobicistat
• Atenolol
• Atenolol; Chlorthalidone
• Atomoxetine
• Atracurium
• Atropine
• Atropine; Benzoic Acid; Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate
• Atropine; Difenoxin
• Atropine; Diphenoxylate
• Atropine; Edrophonium
• Atropine; Hyoscyamine; Phenobarbital; Scopolamine
• Avanafil
• Azelastine
• Azelastine; Fluticasone
• Azilsartan; Chlorthalidone
• Baclofen
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• Belladonna Alkaloids; Ergotamine; Phenobarbital
• Belladonna; Opium
• Benazepril; Hydrochlorothiazide, HCTZ
• Bendroflumethiazide; Nadolol
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• Bethanechol
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• Bosentan
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• Brimonidine; Timolol
• Bromocriptine
• Brompheniramine; Carbetapentane; Phenylephrine
• Brompheniramine; Guaifenesin; Hydrocodone
• Brompheniramine; Hydrocodone; Pseudoephedrine
• Brompheniramine; Pseudoephedrine
• Budesonide
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• Bumetanide
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• Butorphanol
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• Cannabidiol
• Capecitabine
• Capsaicin; Metaxalone
• Captopril; Hydrochlorothiazide, HCTZ
• Carbetapentane; Chlorpheniramine
• Carbetapentane; Chlorpheniramine; Phenylephrine
• Carbetapentane; Diphenhydramine; Phenylephrine
• Carbetapentane; Guaifenesin
• Carbetapentane; Guaifenesin; Phenylephrine
• Carbetapentane; Phenylephrine
• Carbetapentane; Phenylephrine; Pyrilamine
• Carbetapentane; Pseudoephedrine
• Carbetapentane; Pyrilamine
• Carbidopa; Levodopa; Entacapone
• Carbinoxamine; Dextromethorphan; Pseudoephedrine
• Carbinoxamine; Hydrocodone; Phenylephrine
• Carbinoxamine; Hydrocodone; Pseudoephedrine
• Carbinoxamine; Pseudoephedrine
• Cardiac glycosides
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• Carteolol
• Carvedilol
• Celecoxib
• Cenobamate
• Cetirizine
• Cetirizine; Pseudoephedrine
• Chlophedianol; Dexchlorpheniramine; Pseudoephedrine
• Chlordiazepoxide
• Chlordiazepoxide; Clidinium
• Chlorothiazide
• Chlorpheniramine; Codeine
• Chlorpheniramine; Dihydrocodeine; Phenylephrine
• Chlorpheniramine; Dihydrocodeine; Pseudoephedrine
• Chlorpheniramine; Guaifenesin; Hydrocodone; Pseudoephedrine
• Chlorpheniramine; Hydrocodone
• Chlorpheniramine; Hydrocodone; Phenylephrine
• Chlorpheniramine; Hydrocodone; Pseudoephedrine
• Chlorpheniramine; Pseudoephedrine
• Chlorpromazine
• Chlorthalidone
• Chlorthalidone; Clonidine
• Chlorzoxazone
• Ciclesonide
• Cisatracurium
• Clevidipine
• Clobazam
• Clonazepam
• Clonidine
• Clorazepate
• Clozapine
• Cobicistat
• Cocaine
• Codeine
• Codeine; Guaifenesin
• Codeine; Phenylephrine; Promethazine
• Codeine; Promethazine
• Colchicine
• Colchicine; Probenecid
• COMT inhibitors
• Corticosteroids
• Corticotropin, ACTH
• Cortisone
• Cyclobenzaprine
• Dantrolene
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• Dapagliflozin; Metformin
• Dapagliflozin; Saxagliptin
• Darunavir; Cobicistat
• Darunavir; Cobicistat; Emtricitabine; Tenofovir alafenamide
• Dasabuvir; Ombitasvir; Paritaprevir; Ritonavir
• Deflazacort
• Desloratadine
• Desloratadine; Pseudoephedrine
• Desmopressin
• Deutetrabenazine
• Dexamethasone
• Dexchlorpheniramine; Dextromethorphan; Pseudoephedrine
• Dexmedetomidine
• Dexmethylphenidate
• Dextroamphetamine
• Dextromethorphan; Guaifenesin; Pseudoephedrine
• Dextromethorphan; Promethazine
• Dextromethorphan; Quinidine
• Diazepam
• Diethylpropion
• Digitoxin
• Digoxin
• Dihydrocodeine; Guaifenesin; Pseudoephedrine
• Dihydroergotamine
• Diltiazem
• Dipeptidyl Peptidase-4 Inhibitors
• Diphenhydramine; Hydrocodone; Phenylephrine
• Disopyramide
• Donepezil
• Donepezil; Memantine
• Dorzolamide; Timolol
• Doxacurium
• Doxazosin
• Doxercalciferol
• Doxorubicin
• Dronabinol
• Dronedarone
• Droperidol
• Dulaglutide
• Dutasteride; Tamsulosin
• Dyphylline
• Dyphylline; Guaifenesin
• Elexacaftor; tezacaftor; ivacaftor
• Eliglustat
• Elvitegravir
• Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Alafenamide
• Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Disoproxil Fumarate
• Empagliflozin
• Empagliflozin; Linagliptin
• Empagliflozin; Linagliptin; Metformin
• Empagliflozin; Metformin
• Enalapril; Felodipine
• Enalapril; Hydrochlorothiazide, HCTZ
• Enflurane
• Entacapone
• Epinephrine
• Epoprostenol
• Eprosartan; Hydrochlorothiazide, HCTZ
• Ergoloid Mesylates
• Ergonovine
• Ergot alkaloids
• Ergotamine
• Ertugliflozin
• Ertugliflozin; Metformin
• Ertugliflozin; Sitagliptin
• Esketamine
• Esmolol
• Estazolam
• Eszopiclone
• Ethacrynic Acid
• Ethanol
• Etomidate
• Exenatide
• Ezogabine
• Felodipine
• Fenofibric Acid
• Fentanyl
• Fexofenadine; Pseudoephedrine
• Flibanserin
• Fludrocortisone
• Flunisolide
• Fluoxetine; Olanzapine
• Fluphenazine
• Flurazepam
• Fluticasone
• Fluticasone; Salmeterol
• Fluticasone; Umeclidinium; Vilanterol
• Fluticasone; Vilanterol
• Formoterol
• Formoterol; Mometasone
• Fosinopril; Hydrochlorothiazide, HCTZ
• Fospropofol
• Furosemide
• Gabapentin
• Galantamine
• Gentamicin
• Ginger, Zingiber officinale
• Glimepiride; Pioglitazone
• Glimepiride; Rosiglitazone
• Glipizide; Metformin
• Glyburide; Metformin
• Glycopyrrolate; Formoterol
• Green Tea
• Guaifenesin; Hydrocodone
• Guaifenesin; Hydrocodone; Pseudoephedrine
• Guaifenesin; Pseudoephedrine
• Guanabenz
• Halogenated Anesthetics
• Haloperidol
• Halothane
• Heparin
• Homatropine; Hydrocodone
• Hyaluronidase
• Hyaluronidase, Recombinant; Immune Globulin
• Hydantoins
• Hydralazine; Hydrochlorothiazide, HCTZ
• Hydrochlorothiazide, HCTZ
• Hydrochlorothiazide, HCTZ; Irbesartan
• Hydrochlorothiazide, HCTZ; Lisinopril
• Hydrochlorothiazide, HCTZ; Losartan
• Hydrochlorothiazide, HCTZ; Methyldopa
• Hydrochlorothiazide, HCTZ; Metoprolol
• Hydrochlorothiazide, HCTZ; Moexipril
• Hydrochlorothiazide, HCTZ; Olmesartan
• Hydrochlorothiazide, HCTZ; Propranolol
• Hydrochlorothiazide, HCTZ; Quinapril
• Hydrochlorothiazide, HCTZ; Spironolactone
• Hydrochlorothiazide, HCTZ; Telmisartan
• Hydrochlorothiazide, HCTZ; Triamterene
• Hydrochlorothiazide, HCTZ; Valsartan
• Hydrocodone
• Hydrocodone; Ibuprofen
• Hydrocodone; Phenylephrine
• Hydrocodone; Potassium Guaiacolsulfonate
• Hydrocodone; Potassium Guaiacolsulfonate; Pseudoephedrine
• Hydrocodone; Pseudoephedrine
• Hydrocortisone
• Hydromorphone
• Ibuprofen; Oxycodone
• Ibuprofen; Pseudoephedrine
• Iloperidone
• Iloprost
• Incretin Mimetics
• Indacaterol
• Indacaterol; Glycopyrrolate
• Indapamide
• Insulin Degludec; Liraglutide
• Insulin Glargine; Lixisenatide
• Insulins
• Iobenguane I 131
• Ionic Contrast Media
• Isocarboxazid
• Isoflurane
• Isradipine
• Ivacaftor
• Kanamycin
• Ketamine
• Labetalol
• Lasmiditan
• Levalbuterol
• Levobetaxolol
• Levobunolol
• Levocetirizine
• Levomethadyl
• Levorphanol
• Levothyroxine
• Levothyroxine; Liothyronine (Porcine)
• Levothyroxine; Liothyronine (Synthetic)
• Linagliptin; Metformin
• Linezolid
• Liothyronine
• Liraglutide
• Lithium
• Lixisenatide
• Lofexidine
• Loop diuretics
• Lopinavir; Ritonavir
• Loratadine
• Loratadine; Pseudoephedrine
• Lorazepam
• Loxapine
• Luliconazole
• Lumacaftor; Ivacaftor
• Lumacaftor; Ivacaftor
• Lumateperone
• Lurasidone
• Macitentan
• Magnesium Salts
• Maprotiline
• Mecamylamine
• Meclizine
• Meglitinides
• Meperidine
• Meperidine; Promethazine
• Mephobarbital
• Meprobamate
• Metaproterenol
• Metaxalone
• Metformin
• Metformin; Pioglitazone
• Metformin; Repaglinide
• Metformin; Rosiglitazone
• Metformin; Saxagliptin
• Metformin; Sitagliptin
• Methadone
• Methamphetamine
• Methocarbamol
• Methohexital
• Methyclothiazide
• Methyldopa
• Methylergonovine
• Methylphenidate
• Methylprednisolone
• Methysergide
• Metoclopramide
• Metolazone
• Metoprolol
• Metyrapone
• Metyrosine
• Midazolam
• Midodrine
• Miglitol
• Minocycline
• Mirabegron
• Mirtazapine
• Mitotane
• Mivacurium
• Molindone
• Mometasone
• Monoamine oxidase inhibitors
• Morphine
• Morphine; Naltrexone
• Nabilone
• Nadolol
• Nafarelin
• Nalbuphine
• Naproxen; Pseudoephedrine
• Nebivolol
• Nebivolol; Valsartan
• Nefazodone
• Neuromuscular blockers
• Nicardipine
• Nicotine
• Nifedipine
• Nimodipine
• Nisoldipine
• Nitrates
• Non-Ionic Contrast Media
• Olanzapine
• Ombitasvir; Paritaprevir; Ritonavir
• Opiate Agonists
• Oritavancin
• Orphenadrine
• Oxazepam
• Oxycodone
• Oxymorphone
• Oxytocin
• Paliperidone
• Pancuronium
• Papaverine
• Paromomycin
• Paroxetine
• Peginterferon Alfa-2b
• Penbutolol
• Pentazocine
• Pentazocine; Naloxone
• Pentobarbital
• Perampanel
• Pergolide
• Perindopril; Amlodipine
• Perphenazine
• Perphenazine; Amitriptyline
• Phendimetrazine
• Phenelzine
• Phenobarbital
• Phenothiazines
• Phenoxybenzamine
• Phentermine
• Phentermine; Topiramate
• Phentolamine
• Phenylephrine; Promethazine
• Phosphodiesterase inhibitors
• Pimozide
• Pindolol
• Pioglitazone
• Pirbuterol
• Pitolisant
• Plazomicin
• Potassium-sparing diuretics
• Pramipexole
• Pramlintide
• Prazosin
• Prednisolone
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• Pregabalin
• Prilocaine; Epinephrine
• Primidone
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• Propofol
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• Quazepam
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• Racepinephrine
• Ramelteon
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