Drug Side Effects and Interactions

Allergy / Reactivity / Cross Sensitivity

“I’m Allergic to Penicillin” – Prescribing pointers
When a penicillin is indicated in these people, what choices can prescribers make? Is it better to substitute a drug with potentially more serious side-effects even if the reaction to a penicillin has been mild?
http://www.nps.org.au/__data/assets/pdf_file/0007/15784/news15_urtis_antibiotics_0401.pdf

‘Sulfur allergy’ label is misleading
The term ‘sulfur allergy’ is misleading and dangerous and should not be used. An allergy to a sulfonamide antibiotic may imply cross-reactivity with other sulfonamide antibiotics, but does not imply cross-reactivity with non-antibiotic sulfonamides or other drugs containing sulfhydryl or sulfate groups.
http://www.australianprescriber.com/magazine/31/1/8/10

All Allergy Net
Monthly newsletter of recent journal articles related to food allergy, allergens and substances involved in allergy or intolerance reactions
http://www.allallergy.net/

Allergy & Immunology Chapters
Allergy Online Medical References, part of the Disease Management Project published by the Cleveland Clinic Center for Continuing Education.
http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/allergy/

Allergy Advisor Educational Review
Allergy Advisor – Allergy and Intolerance Software for diagnosis and management; from Allergy Resources International, Zing Solutions.
http://www.allergyadvisor.com/educational/index.html

Anaphylaxis Review: What Pharmacists Need to Know
Anaphylaxis Review: What Pharmacists Need to Know Kyle R. Copeland , PharmD Educational Objectives Upon completion of this educational activity, participants should be able to: Describe the pathophysiology of and risk factors for anaphylaxis.
http://www.ikatanapotekerindonesia.net/articles/pharma-update/pharmaceutical-research/1517-anaphylaxis-review-what-pharmacists-need-to-know.html

Anticonvulsant Hypersensitivity Syndrome
Anticonvulsant Hypersensitivity Syndrome occurs in some patients taking anticonvulsant medication. It is characterised by fever, rash, hepatitis and other multiorgan abnormalities. The mechanism is unknown. Patients who have experienced this syndrome should not receive anticonvulsants in the phenytoin category, carbamazepine, phenobarbitone and lamotrigine.
http://www.medsafe.govt.nz/Profs/PUarticles/6.htm

Antiepileptic hypersensitivity syndrome
Antiepileptic hypersensitivity syndrome (AHS), formally known as “hydantoin hypersensitivity syndrome,” is a severe idiosyncratic cutaneous reaction to aromatic anticonvulsants that can potentially result in end organ damage and death.
https://web.archive.org/web/20060524040059/http://www.shands.org/professional/drugs/bulletins/0500.pdf

Cross-reactivity of beta-lactam antibiotics
During a drug history, the most common drug allergies cited are those experienced after the administration of a penicillin, with a reported allergy incidence of 1% to 10% in patients who receive drugs in this class.
http://www.baylorhealth.edu/Documents/BUMC%20Proceedings/2001%20Vol%2014/No.%201/14_1_%20James.pdf

Drug Allergy Information Sheet
Adverse reactions to drugs may result from a number of properties of the drug, to drug over-dosage, to intolerance to the drug, or due to a true allergy against the drug.
https://web.archive.org/web/*/http://www.allergysa.org/pdfs/info-sheets/DRUG%20ALLERGY.pdf

Drug Hypersensitivity Syndrome
Drug Hypersensitivity Syndrome is potentially life-threatening with significant morbidity. It is characterised by fever, rash and internal organ involvement. Prompt diagnosis is vital, along with identification and early withdrawal of suspect medicines. Avoidance of re-exposure to the responsible agent is essential.
http://www.medsafe.govt.nz/Profs/PUarticles/DHS.htm

Drug-induced Photosensitivity
Drug-induced photosensitivity refers to the development of cutaneous disease as a result of the combined effects of a chemical and light.
http://emedicine.medscape.com/article/1049648-overview

Drug-induced photosensitivity
This page includes the following topics and synonyms: Drug-induced Photosensitivity, Photosensitizer, Medication Causes of Phototoxic Reaction, Phytodermatitis, Phytophotodermatitis.
http://www.fpnotebook.com/legacy/Derm/Pharm/DrgIndcdPhtsnstvty.htm

Examining Penicillin Allergies
An Examination of Penicillin Allergy. Resident Grand Rounds February 12, 2002 David H. Priest, MD. Outline. Introduction What is a true penicillin allergy? How can we determine who is truly allergic? – PowerPoint PPT Presentation
http://www.slideserve.com/lester/an-examination-of-penicillin-allergy

Food allergy
10­minute consultation:
A newly qualified teacher requests investigations for possible food allergies. She has been troubled with symptoms of tiredness, nausea, bloating, and intermittent diarrhoea. Bread and chocolate have been identified as possible triggers, and reducing intake of these foods has resulted in some improvement of symptoms. General physical examination is unremarkable.
http://www.bmj.com/cgi/reprint/325/7376/1337

Glucosamine and Shellfish Allergy
Can patients take glucosamine to treat arthritis if they are allergic to shellfish?
http://professionals.ufhealth.org/files/2011/11/0604-drugs-therapy-bulletin.pdf

Immunotherapy for allergic disorders
Immunotherapy can be an effective and safe treatment for reducing allergic reactivity to a number of inhaled and injected allergens.
http://www.australianprescriber.com/magazine/26/4/91/3/

Latex Allergy 101
To highlight the complexity of latex allergy the Latex Allergy 101 Program was developed. The Program consist of a Latex Allergy 101 Poster and four fact sheets Allergy, Anaphylaxis, Asthma, Food Allergy. The Fact sheets were developed by experts in each of the specialized fields.
http://latexallergyresources.org/latex-allergy-101

Classification of Local Anesthetic agent
Local anesthetic agents can be grouped based on their chemical structure. Following are the chemical groups of local anesthetics commonly used in dentistry which are classified accordingly based on their chemical structure.<
http://www.juniordentist.com/classification-of-local-anesthetic-agent.html

Minimizing “Allergic” Reactions to Contrast Media
Clinicians often wonder what risk factors they should consider when trying to manage patients who may have a reaction to radiopaque contrast media.
http://professionals.ufhealth.org/files/2011/11/0904-drugs-therapy-bulletin.pdf

National Institute of Allergy and Infectious Diseases
NIAID conducts and supports basic and applied research to better understand, treat, and ultimately prevent infectious, immunologic, and allergic diseases.
http://www.niaid.nih.gov/

NSAID Chemical Classification
Classification of non-steroidal anti-inflammatory drugs (NSAIDs)
http://www.vhpharmsci.com/VHFormulary/Tools/NSAID-Classification.htm

Opioid Analgesics Chemical Classification
http://www.vhpharmsci.com/vhformulary/Tools/Chemical%20Classification%20of%20Opioids.pdf

Drug-induced Pruritus
Pruritus is an unpleasant sensation that leads to scratching. In addition to several diseases, the administration of drugs may induce pruritus. It is estimated that pruritus accounts for approximately 5% of all skin adverse reactions after drug intake.
http://www.medicaljournals.se/acta/content/?doi=10.2340/00015555-0650&html=1

Peanut Allergy
http://www.medsafe.govt.nz/Profs/PUarticles/peanut.htm

Preventing Allergic Reactions to Drugs
Documenting and reporting drug allergies is a multidisciplinary process involving several steps. During the patient’s initial assessment, the physician questions the patient about his allergy history.
https://web.archive.org/web/20060720164037/http://www.shands.org/professional/drugs/bulletins/0803.pdf

Sulfonamide Cross-Sensitivity Reactions
Approximately 3% of the general population has a hypersensitivity reaction to sulfonamide antimicrobials.
http://web.archive.org/web/20040603160519/www.vh.org/adult/provider/pharmacyservices/RXUpdate/2003/07rxu.html

Sulphur Allergy
There is much confusion about what constitutes “sulfur allergy” and its clinical significance. We are often asked, “Can a patient with a sulfur allergy have medication containing sulfur?” and, “What other drugs is the patient likely to be allergic to?” This bulletin discusses the meaning of “sulfur allergy”.
http://www.druginformation.co.nz/Bulletins/SulphurAllergy.pdf

Testing for Drug Allergy
Drug allergy is a significant problem in medical practice. The diagnosis is made primarily from the clinical history as there are few specific, accurate diagnostic tests. If a patient has a drug allergy, alternative drugs should be used in the future. However, if the particular drug is considered essential in subsequent therapy, various techniques may allow its use.
http://www.australianprescriber.com/magazine/17/3/62/5/

Update on the OTC Treatment of Allergies: Focus on Allergic Conjunctivitis
As many as 50 million individuals in the United States suffer from various forms of allergic conditions, including indoor/outdoor, food and drug, dermatologic, and ocular allergies.
https://web.archive.org/web/20111111045507/https://secure.pharmacytimes.com/lessons/200903-02.asp

Using diuretics in patients with sulfa allergies
Sulfonamide allergies are com- monly reported. These reactions are usually associated with sulfonamide antibiotics. However, prescribers are often faced with problems caused by the potential for cross-reactivity with other sulfonamide drugs.
http://professionals.ufhealth.org/files/2011/11/0303-drugs-therapy-bulletin.pdf

Drug Interaction

Cytochrome P450 Drug Interactions
http://medicine.iupui.edu/clinpharm/ddis/

Drug Interactions Checker
Check for drug interactions and learn what drug combinations to avoid with the RxList drug interaction checker tool.
http://www.rxlist.com/drug-interaction-checker.htm

Drugs.com – Drug Interactions Checker
Check for multi-drug interactions including alcohol, food, supplements & diseases. Includes detailed reports for both patients and health professionals.
http://www.drugs.com/drug_interactions.html

Food-Drug Interactions: Coumadin® and Vitamin K
https://ods.od.nih.gov/pubs/factsheets/coumadin1.pdf

AIDS drugs interactions tables
http://www.hivclinic.ca/main/drugs_interact.html

Clinically Important Features of CYP2D6
http://www.druginformation.co.nz/Bulletins/CytochromeP4502D6.pdf

Drug Digest (Multicheck)
https://www.express-scripts.com/medco/consumer/ehealth/druginfo/dlmain.jsp?WC=N

Drug Interactions Associated with Antidepressant Use
In relation to drug interactions, 2 types exist: pharmacokinetic and pharmacodynamic. Pharmacokinetic interactions occur when 1 medication (the precipitant drug) changes the absorption, distribution (including protein binding), metabolism, or excretion of another medication (the object drug), resulting in altered concentrations of the object drug.
http://inetce.com/articles/pdf/221-999-05-005-H01.pdf

Drug Interactions with Fruit Juices
http://www.druginformation.co.nz/Bulletins/DrugInteractionsWithFruitJuices_June2006.pdf

G6PD Deficiency and Drug Interaction
G6PD Deficiency
http://www.globalrph.com/g6pd.htm

Grapefruit Drug Interaction
Drug interactions with grapefruit. Clinical significance.
http://www.globalrph.com/gfruit.htm

Drug Interactions with Grapefruit Juice
Grapefruit juice affects how some drugs are changed in the body for eventual elimination.
http://www.drugs.com/article/grapefruit-drug-interactions.html

HIV Drug Interactions
http://www.hiv-druginteractions.org/

Interactions Between Herbs and Cardiac Medications
http://www.clevelandclinicmeded.com/medicalpubs/pharmacy/MarApr2001/herbs_cardiac.htm

Interactions with Systemic Antifungals
http://www.druginformation.co.nz/Bulletins/AntifungalDrugInteractions_bulletin.pdf

P-glycoprotein and its role in drug-drug interactions
http://www.australianprescriber.com/magazine/37/4/137/9

Herbal Medicinals – Selected Clinical Considerations Focusing on Known or Potential Drug-Herb Interactions
Review from JAMA Internal Medicine — Herbal Medicinals — Selected Clinical Considerations Focusing on Known or Potential Drug-Herb Interactions
http://archinte.jamanetwork.com/article.aspx?articleid=210330

Top 10 Particularly Dangerous Drug Interactions in Long Term Care
http://www.amda.com/tools/clinical/m3/topten.cfm

Drug Safety & Warnings

Australian Medicines Safety Update
Medicines Safety Update provides practical information and advice on drug safety and information about emerging safety issues.
http://www.tga.gov.au/publication/medicines-safety-update

Center for Adverse Drug Monitoring – New Zealand
https://nzphvc.otago.ac.nz/

Drug Eruption Global Database
We allow you to search the profiles of thousands of generic and trade name drugs, while also providing over 60,000 references that link directly to PubMed, enabling you to better diagnose and treat your patients.
http://www.drugeruptiondata.com/

European Agency for the Evaluation of Medicinal Products (EMEA)
European Union agency responsible for the protection of public and animal health through the scientific evaluation and supervision of medicines.
http://www.ema.europa.eu/ema/

ISMP – Canada
http://www.ismp-canada.org/

ISMP Medication Safety Alert – US
The Institute for Safe Medication Practices (ISMP) is devoted entirely to medication error prevention and safe medication use. ISMP represents over 30 years of experience in helping healthcare practitioners keep patients safe, and continues to lead efforts to improve the medication use process. The organization is known and respected worldwide as the premier resource for impartial, timely, and accurate medication safety information.
http://www.ismp.org/

Medical Errors & Patient Safety – Agency for Healthcare Research and Quality (AHRQ)
http://www.ahrq.gov/professionals/quality-patient-safety/patient-safety-resources/index.html

Medicines and Healthcare products Regulatory Agency
The Medicines and Healthcare products Regulatory Agency regulates medicines, medical devices and blood components for transfusion in the UK.
https://www.gov.uk/government/organisations/medicines-and-healthcare-products-regulatory-agency

Monitoring the safety and quality of medicines
http://www.mhra.gov.uk/home/groups/comms-ic/documents/websiteresources/con2031677.pdf

New Zealand Medicines and Medical Devices Safety Authority (Medsafe)
http://www.medsafe.govt.nz/

Swedish Medical Products Agency (MPA)
The Medical Products Agency (MPA) is the Swedish national authority responsible for regulation and surveillance of the development, manufacturing and sale of drugs and other medicinal products.
https://lakemedelsverket.se/english/

Uppsala Monitoring Centre – WHO
http://www.who-umc.org/

US-FDA Center for Drug Evaluation and Research (CDER)
http://www.fda.gov/Drugs/default.htm

US-FDA MedWatch – Medical Product Safety Information
http://www.fda.gov/Safety/MedWatch/SafetyInformation/default.htm

WHO Drug Alerts
http://www.who.int/medicines/publications/drugalerts/en/

WHO Pharmaceuticals Newsletter
http://www.who.int/medicines/publications/newsletter/en/

WHO Medicines Safety
http://www.who.int/medicines/areas/quality_safety/safety_efficacy/en/

Drug-Induced Symptoms

Adverse Respiratory Reactions to Long-acting Beta-agonists
http://www.medsafe.govt.nz/Profs/PUarticles/laba.htm

Alendronate and Oesophageal Ulceration
http://www.medsafe.govt.nz/Profs/PUarticles/7.htm

Atypical antipsychotic-induced blood dyscrasias
http://www.druginformation.co.nz/Bulletins/AtypicalAntipsychotics_blood.pdf

Atypical Antipsychotics May Cause Hypertension
http://www.medsafe.govt.nz/Profs/PUarticles/aahyp.htm

Beta Blockers and Airway Disease
http://professionals.ufhealth.org/files/2011/11/0603-drugs-therapy-bulletin.pdf

Carbamazepine induced Blood Dyscrasias and Skin Rash
http://www.medsafe.govt.nz/Profs/PUarticles/carbam.htm

Diarrhoea with Beta-Blockers
http://www.medsafe.govt.nz/Profs/PUarticles/BBdiarrhoea.htm

Drug Induced Hyponatraemia
http://www.druginformation.co.nz/Bulletins/DrugInducedHyponatraemia.pdf

Drug Induced Osteoporosis (DIO)
http://medsask.usask.ca/documents/newsletters/archive/25.1.OP_newsletter.pdf

Drug-Induced Delirium
http://www.druginformation.co.nz/Bulletins/DrugInducedDelirium_bulletin.pdf

Drug-Induced QT Prolongation
http://www.druginformation.co.nz/Bulletins/DrugInducedQTPBulletin.pdf

Drugs & Gastrointestinal Bleeding
http://www.druginformation.co.nz/Bulletins/Drugs&GI-Bleeding_BulletinApril2006.pdf

Guidelines for the Prevention of Contrast-Induced Nephropathy Utilizing Hydration & N-acetylcysteine
http://www.hosp.uky.edu/pharmacy/formulary/criteria/ContrastNephropathyGuidelines.pdf

Hyperprolactinaemia With Antipsychotics
http://www.medsafe.govt.nz/Profs/PUarticles/hyperpro.htm

Medication induced esophagitis
http://professionals.ufhealth.org/files/2011/11/0301-drugs-therapy-bulletin.pdf

Medication Induced Urine Discoloration & Urinalysis
Medications which may cause discoloration of urine (Table)
http://www.globalrph.com/urine.htm

Medication-Induced Discoloration of Feces
Medications which may discolor the stool.
http://www.globalrph.com/feces.htm

Medication-Induced Fever
Medications which may induce fever (Adverse effect).
http://www.globalrph.com/fever.htm

Medication-Induced Hyperglycemia
Medications which may induce hyperglycemia (increased blood sugars) (Adverse effect).
http://www.globalrph.com/glycemia.htm

Medication-Induced Hyperuricemia
Drug-induced hyperuricemia.
http://www.globalrph.com/uricacid.htm

Medication-Induced Neutropenia
Medications which may reduce the neutrophil count (neutropenia).
http://www.globalrph.com/neutropenia.htm

Medication-Induced Thrombocytopenia
platelets, thrombocytopenia, reduced platelet count, hematological side effects
http://www.globalrph.com/thrombo.htm

Serotonin Syndrome: Recognition and Management
Serotonin syndrome is a potentially life-threatening condition caused by excessive serotonergic activity in the nervous system. It is characterized by mental status changes, autonomic instability, and neuromuscular hyperactivity.
http://www.aafp.org/afp/2010/0501/p1139.html

The truth about drug fever
http://professionals.ufhealth.org/resources/drug-information-and-pharmacy-resource-center/bulletins/

Medication Error

10 Strategies to Reduce Medication Errors
http://www.fda.gov/Drugs/ResourcesForYou/Consumers/ucm143553.htm

ASHP Guidelines on Preventing Medication Errors in Hospitals
http://www.ashp.org/DocLibrary/BestPractices/MedMisGdlHosp.aspx

Attacking the Medication Error Problem
http://www.safer.healthcare.ucla.edu/gl/pdf/MedErrors_HolyCross.pdf

ISMP’s List of Confused Drug Names
https://www.ismp.org/tools/confuseddrugnames.pdf

Guidelines for Preventing Medication Errors in Pediatrics
http://www.ismp.org/Newsletters/acutecare/articles/20020601.asp

Learning from Medication Errors
Home PJ (Current issue) Meetings and Conferences
http://www.pharmaceutical-journal.com/pj-online-tackling-medication-errors-learning-from-our-mistakes/20007968.article

Medication Errors
http://www.fda.gov/Drugs/DrugSafety/MedicationErrors/default.htm

Medication Tools and Safety Resources
http://www.ismp.org/Tools/

Preventing Inadvertent IV Administration of Nimodopine Capsule Contents
Success with New Year’s resolutions requires more than personal resolve
https://www.ismp.org/newsletters/acutecare/articles/20050728_1.asp

Sound alike look alike medication to be aware of list
http://pharmacy.uchc.edu/references/docs/list_look_alikes.pdf

Strategies for Preventing Medication Misadventures: Impact on Insulin Safety
http://www.cecity.com/jobson/new_strategy/flash.htm

The Pharmacist’s Role in a Quality System to Prevent Medication Errors
http://www.rxschool.com/Outside/CE/pharmacy_law_roll_of_pharmacists.cfm

The Pharmacy Technician – A Key to Reducing Medication Errors Part 1
http://www.rxschool.com/Outside/CE/pharmacy_technician_law_part_one.cfm

The Pharmacy Technician – A Key to Reducing Medication Errors Part 2
http://www.rxschool.com/Outside/CE/pharmacy_technician_law_part_two.cfm

The Pharmacy Technician – A Key to Reducing Medication Errors Part 3
http://www.rxschool.com/Course/info.cfm?COURSE_ID=113

Wrong-Patient Medication Errors: An Analysis of Event Reports in Pennsylvania and Strategies for Prevention
http://patientsafetyauthority.org/ADVISORIES/AdvisoryLibrary/2013/Jun;10%282%29/Pages/41.aspx

Poison Control & Toxicology

Guidelines for poison control – WHO
http://www.who.int/ipcs/publications/training_poisons/guidelines_poison_control/en/index7.html

Toxic Substances Portal
The Agency for Toxic Substances and Disease Registry (ATSDR), based in Atlanta, Georgia, is a federal public health agency of the U.S. Department of Health and Human Services. ATSDR serves the public by using the best science, taking responsive public health actions, and providing trusted health information to prevent harmful exposures and diseases related to toxic substances.
http://www.atsdr.cdc.gov/

TOXNET
Toxicology, environmental health, and chemical databases and other information resources from the Toxicology and Environmental Health Information Program, National Library of Medicine, National Institutes of Health
http://toxnet.nlm.nih.gov/

AACT – American Academy of Clinical Toxicology
The American Academy of Clinical Toxicology (AACT) is a not-for-profit multi-disciplinary organization uniting scientists and clinicians in the advancement of research, education, prevention and treatment of diseases caused by chemicals, drugs and toxins.
http://www.clintox.org/

Agency for Toxic Substances and Disease Registry (ATSDR) Tox FAQs
The ATSDR ToxFAQs is a series of summaries about hazardous substances developed by the ATSDR Division of Toxicology. Information for this series is excerpted from the ATSDR Toxicological Profiles and Public Health Statements. Each fact sheet serves as a quick and easy to understand guide.
http://www.atsdr.cdc.gov/toxfaqs/index.asp

American Association of Poison Control Centers (AAPCC)
http://www.aapcc.org/

Antidote chart California Poison Control System
http://www.calpoison.org/hcp/ANTIDOTE_CHART_2012.pdf

Arizona Poison and Drug Information Center Home
http://tonic.pharmacy.arizona.edu/centers/arizona-poison-drug-information-center

Consumer Products Safety – Health Canada
Health Canada’s role in consumer product safety; links to health risk and safety hazard information, research, reports, advisories, recalls, safety testing, and legislation with topical content related to children’s, household, cosmetic, pest management and recreational products
http://www.hc-sc.gc.ca/cps-spc/index-eng.php

Cornell University Poisonous Plants Home Page
Department of Animal Science at Cornell University; This site contains information about plants which are poisonous to or adversely affect animal health.
http://poisonousplants.ansci.cornell.edu/

EXTOXNET – The Extension Toxicology Network
http://extoxnet.orst.edu/ghindex.html

Infants of Drug-Abusing Mothers
Jeffrey L. Segar, MD
http://www.uichildrens.org/childrens-content.aspx?id=234413

Know Your Plants – Poisoning
http://www.calpoison.org/hcp/KNOW%20YOUR%20PLANTS-plant%20list%20for%20CPCS%2009B.pdf

Medline Plus: Poisoning
Poisoning
https://www.nlm.nih.gov/medlineplus/poisoning.html

MSDS-SEARCH – The National MSDS Repository
The First Place to Look for an MSDS, MSDSSEARCH is the most comprehensive single address for
free information related to the document known as a Material Safety Data Sheet (MSDS), providing access to over 2,500,000 MSDSs, 6000 links
directly to manufacturers, plus links to databases, software vendors, and government sources and organizations.
http://www.msdssearch.com/

Side Effects and Managements

Blood and Marrow Transplant Program – Supportive Care Guidelines
http://hemonc.medicine.ufl.edu/files/2012/11/SupportiveCareGuidelines.pdf

Beta Blockers and Airway Disease
http://professionals.ufhealth.org/files/2011/11/0603-drugs-therapy-bulletin.pdf

Preventing Allergic Reactions to Drugs
DefinitionDrug allergies are a group of symptoms caused by an allergic reaction to a drug (medication).Alternative NamesAllergic reaction – drug (medication); Drug hypersensitivity; Medication hypersensitivityCausesAdverse reactions to drugs are common. (adverse means unwanted or unexpected.) Almost any drug can cause an adverse reaction. Reactions range from irritating or mild side effects such as nausea and vomiting to life-threatening anaphylaxis.
https://ufhealth.org/drug-allergies

Preventing Nosebleeds from Nasal Steroids
http://professionals.ufhealth.org/files/2011/11/0304-drugs-therapy-bulletin.pdf

Viagra Side Effects (Sildenafil)
Learn about the potential side effects of Viagra (sildenafil). Includes common and rare side effects information for consumers and healthcare professionals.
http://www.drugs.com/sfx/viagra-side-effects.html

Cancer Side Effects and Their Management
Cancer and cancer treatment often cause a variety of side effects. Talk with your doctor about which side effects are likely based on your specific treatment plan. An important part of cancer care is relieving side effects, called symptom management, palliative care, or supportive care. It is important to talk with your health care team about the specific side effects you experience and the best ways to manage and treat them.
http://www.cancer.net/navigating-cancer-care/side-effects