The 20 most dangerous drugs

While overdose deaths from prescription opioids have nearly quadrupled since 1999, some of the most dangerous drugs don’t require a prescription.

Using data from the Food and Drug Administration for 2004 through 2015, HealthGrove looked at the 150 drugs that are involved in the highest number of adverse reactions and ranked them by the percent of these reactions classified as serious. For many of these reactions, the FDA database uses medical terminology, such as pyrexia and dyspnoea for fever and labored breathing, respectively.

The top 50 drugs with the most serious adverse reactions are considered the most dangerous. Though most on the list require a prescription and treat serious diseases, those like Advil and acetaminophen don’t.

It’s important to note that these medicines may not be inherently dangerous, but improper dosage, combining medicines or taking them with substances like alcohol can dramatically increase risk.

One-third of Americans say they “combine medications when treating multiple symptoms,” according to the National Council on Patient Information, cited in a New York Times report on over-the-counter medicines. The same source also claims that only one in ten people read the labels entirely and one in five admits to using medication more than the label indicates. This creates an environment primed for unintended drug interactions and overdoses.

Additionally, people over 65 years old — those most likely to take multiple drugs for chronic health issues — account for approximately 40 percent of over-the-counter drug usage. This puts this group at greater risk for trouble with these drugs by way of adverse side effects and interactions.

Despite the potential for negative consequences of drug use and misuse, modern pharmaceuticals have greatly contributed to the health and longevity of people around the world. Though many are regarded as safe, as more drugs become available over the counter and prescriptions of others rise, consumer awareness becomes increasingly important.

Note: In the case of ties, the drug with the highest number of total reported reactions is ranked higher.

#20. Digoxin


 



Percent of Reactions That Were Serious: 83%
Number of Serious Reactions: 30,355
Total Number of Reported Reactions: 36,506
Therapeutic Class: Cardiovascular Agent
Brand Names: Digitek, Digox, Lanoxicaps, Lanoxin, Lanoxin Pediatric, Digitaline Nativelle

#19. Spironolactone


 



Percent of Reactions That Were Serious: 84%
Number of Serious Reactions: 28,871
Total Number of Reported Reactions: 34,336
Therapeutic Class: Cardiovascular Agent
Brand Names: Aldactone

#18. Allopurinol


 



Percent of Reactions That Were Serious: 84%
Number of Serious Reactions: 30,921
Total Number of Reported Reactions: 36,755
Therapeutic Class: Antigout
Brand Names: Aloprim

#17. Morphine


 



Percent of Reactions That Were Serious: 84%
Number of Serious Reactions: 37,986
Total Number of Reported Reactions: 44,906
Therapeutic Class: Analgesic
Brand Names: Avinza, Kadian, Kadian Er, Morphabond, Ms Contin, Msir, Oramorph Sr, Roxanol, Roxanol-T

#16. Ondansetron


 



Percent of Reactions That Were Serious: 85%
Number of Serious Reactions: 31,005
Total Number of Reported Reactions: 36,133
Therapeutic Class: Antiemetic
Brand Names: Zofran, Zofran Odt, Zuplenz

#15. Ramipril


 



Percent of Reactions That Were Serious: 85%
Number of Serious Reactions: 32,374
Total Number of Reported Reactions: 37,895
Therapeutic Class: Antihypertensive
Brand Names: Altace

#14. Rosiglitazone


 



Percent of Reactions That Were Serious: 85%
Number of Serious Reactions: 87,352
Total Number of Reported Reactions: 101,873
Therapeutic Class: Antidiabetic
Brand Names: Avandia

#13. Medroxyprogesterone


 



Percent of Reactions That Were Serious: 89%
Number of Serious Reactions: 34,018
Total Number of Reported Reactions: 38,079
Therapeutic Class: Endocrine-Metabolic Agent
Brand Names: Provera, Alti-Mpa

#12. Lenalidomide


 



Percent of Reactions That Were Serious: 89%
Number of Serious Reactions: 69,123
Total Number of Reported Reactions: 77,417
Therapeutic Class: Immune Modulator
Brand Names: Revlimid

#11. Methylprednisolone


 



Percent of Reactions That Were Serious: 90%
Number of Serious Reactions: 30,040
Total Number of Reported Reactions: 33,095
Therapeutic Class: Endocrine-Metabolic Agent
Brand Names: Medrol, Medrol Dosepak, Methylpred-Dp

#10. Metoclopramide


 



Percent of Reactions That Were Serious: 91%
Number of Serious Reactions: 32,757
Total Number of Reported Reactions: 35,623
Therapeutic Class: Antiemetic
Brand Names: Metozolv Odt, Reglan

#9. Infliximab


 



Percent of Reactions That Were Serious: 91%
Number of Serious Reactions: 68,167
Total Number of Reported Reactions: 74,738
Therapeutic Class: Immunological Agent
Brand Names: Remicade

#8. Tacrolimus


 



Percent of Reactions That Were Serious: 92%
Number of Serious Reactions: 27,964
Total Number of Reported Reactions: 30,262
Therapeutic Class: Antipsoriatic
Brand Names: Protopic

#7. Zoledronic Acid


 



Percent of Reactions That Were Serious: 93%
Number of Serious Reactions: 35,581
Total Number of Reported Reactions: 38,016
Therapeutic Class: Calcium Regulator
Brand Names: Reclast, Zometa

#6. Dexamethasone


 



Percent of Reactions That Were Serious: 93%
Number of Serious Reactions: 38,966
Total Number of Reported Reactions: 41,636
Therapeutic Class: Endocrine-Metabolic Agent
Brand Names: Baycadron Elixer, Decadron, Dekpak 13 Day Taperpak, Dexamethasone Intensol, Dexpak, Dexpak 10 Day Taperpak, Dexpak Jr, Zema-Pak

#5. Clozapine


 



Percent of Reactions That Were Serious: 95%
Number of Serious Reactions: 29,470
Total Number of Reported Reactions: 30,914
Therapeutic Class: Antipsychotic
Brand Names: Clozaril, Fazaclo, Versacloz

#4. Rituximab


 



Percent of Reactions That Were Serious: 96%
Number of Serious Reactions: 30,014
Total Number of Reported Reactions: 31,157
Therapeutic Class: Antineoplastic Agent
Brand Names: Rituxan

#3. Bevacizumab


 



Percent of Reactions That Were Serious: 96%
Number of Serious Reactions: 39,957
Total Number of Reported Reactions: 41,281
Therapeutic Class: Immunological Agent
Brand Names: Avastin

#2. Prednisolone


 



Percent of Reactions That Were Serious: 96%
Number of Serious Reactions: 42,323
Total Number of Reported Reactions: 43,817
Therapeutic Class: Endocrine-Metabolic Agent
Brand Names: Bubbli-Pred, Cotolone, Flo-Pred, Millipred, Millipred Dp, Orapred, Orapred Odt, Pediapred, Prelone, Veripred 20, Pms-Prednisolone

#1. Cyclophosphamide


 



Percent of Reactions That Were Serious: 97%
Number of Serious Reactions: 33,128
Total Number of Reported Reactions: 34,076
Therapeutic Class: Antineoplastic Agent
Brand Names: Cytoxan, Cytoxan Lyophilized

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