the latest in Acne Care
view counter
Subscribe for Free
view counter
Ulcerative Colitis Dementia Resource Back Health Resource Dermatology Resource

Greg McIntosh

 et al.

Dr. Hamilton Hall, MD, FRCSC, is a Professor in the Department of Surgery at the University of Toronto. He is the Medical Director, CBI Health Group and Executive Director of the Canadian Spine Society in Toronto, Ontario.
Greg McIntosh, MSc, completed his Masters in Epidemiology from the University of Toronto's Faculty of Medicine. He is currently the Director of Clinical Research for CBI Health Group and research consultant to the Canadian Spine Society.
Dr. Julia Alleyne, BHSc(PT), MD, CCFP, Dip. Sport Med MScCH, is a Family Physician practising Sport and Exercise Medicine at the Toronto Rehabilitation Institute, University Health Network. She is appointed at the University of Toronto, Department of Family and Community Medicine as an Associate Clinical Professor.
Dr. Pierre Côté, DC, PhD, Canada Research Chair in Disability Prevention and Rehabilitation; Associate Professor, Faculty of Health Sciences, University of Ontario Institute of Technology (UOIT); Director, UOIT-CMCC Centre for the Study of Disability Prevention and Rehabilitation.

Abstract
Neck pain is common and disabling. Associated with poor posture, sedentary work and stress it is long lasting and recurrent. Most neck pain is mechanical from the structural elements within the cervical spine and can be referred to a number of remote locations. Radicular arm dominant pain is infrequent. Neck pain is diagnosed on history and confirmed with the physical examination. Routine imaging is inappropriate and the Canadian C-spine rules are recommended. Management focuses on education, range of movement exercises with associated postural improvement and strengthening exercises; neck braces should not be used.
Key Words: cervical spine, neck pain, Canadian C-spine rules, range of movement, exercise.

Francesca Cheung, MD CCFP, is a family physician with a focused practice designation in dermatology. She received the Diploma in Practical Dermatology from the Department of Dermatology at Cardiff University in Wales, UK. She is practising at the Lynde Institute for Dermatology in Markham, Ontario and works closely with Dr. Charles Lynde, MD FRCPC, an experienced dermatologist. In addition to providing direct patient care, she acts as a sub-investigator in multiple clinical studies involving psoriasis, onychomycosis, and acne. Jeffrey Law and Lindsey Chow, are third year medical students from the University of Western Ontario.

Abstract
Kaposi’s sarcoma (KS) is an angioproliferative tumour that requires infection by Human Herpesvirus 8 (HHV-8). It most commonly affects elderly men of Mediterranean/Eastern European backgrounds and HIV-infected patients. KS presents clinically as lesions on the skin, but may also arise in the gastrointestinal tract, lungs, and lymph nodes. There is no definitive cure for KS; therapeutic goals are to decrease the size of the lesions, prevent progression and improve function. Management depends on the type of KS, extent of disease and overall health of the patient. Observation is acceptable if the patient is asymptomatic; HAART is often sufficient to control lesions in HIV-infected patients. Cryotherapy and local excision can be used to treat solitary symptomatic lesions. Radiation therapy can be used for advanced and extended KS and in those patients for whom surgery is contraindicated. Intra-lesional injection of interferon alpha-2a or chemotherapeutic agents like vincristine have been reported to be effective in treating nodular KS lesions, but may be associated with inflammation and discomfort. Systemic chemotherapy such as pegylated liposomal doxorubicin is indicated when KS is widespread or rapidly progressive. The prognosis for KS is generally great with most patients dying from unrelated causes.
Key Words: Kaposi’s Sarcoma, HHV-8, HIV/ AIDS.

Shannon Humphrey, MD, FRCPC, FAAD, Director of Continuing Medical Education, Clinical Instructor, Department of Dermatology and Skin Science, University of British Columbia, Vancouver, BC, Canada.

Abstract
While topical therapy remains a key therapeutic approach in the clinical management of AV, it can be associated with side effects that may compromise the stratum corneum and impair patient adherence. The use of adjunctive cleansers and moisturizers can help mitigate treatment side effects and subsequently enhance therapeutic efficacy. Providing patient-specific skin care recommendations, including product selection and proper use, is an important part of the clinical management of AV and may adjunctively augment the efficacy of topical medications in reducing acne lesions.
Key Words: acne vulgaris, adherence, cleansers, moisturizers.

Greg McIntosh

 et al.

Dr. Hamilton Hall, MD, FRCSC, is a Professor in the Department of Surgery at the University of Toronto. He is the Medical Director, CBI Health Group and Executive Director of the Canadian Spine Society in Toronto, Ontario.
Greg McIntosh, MSc, completed his Masters in Epidemiology from the University of Toronto's Faculty of Medicine. He is currently the Director of Clinical Research for CBI Health Group and research consultant to the Canadian Spine Society.

Abstract
This article highlights the myths and misunderstandings surrounding the straight leg raise (SLR) test for sciatica. Unfortunately, neither intra- nor inter-observer reliability of the passive SLR test has ever been agreed upon. In addition, there is poor consensus about what constitutes a positive SLR test in terms of pain location, leg elevation limitation or clinical significance. Until there are stricter performance standards and uniform agreement, researchers and clinicians should interpret the test with caution. We believe a true positive SLR should be the reproduction or exacerbation of the typical leg dominant pain in the affected limb at any degree of passive elevation. Those with only increased back pain or any leg pain other than that presenting as the chief complaint should be regarded as false positives.
Key Words: low back pain, straight leg raise, sciatica, irritative test.

Greg McIntosh

 et al.

Dr. Hamilton Hall, MD, FRCSC, is a Professor in the Department of Surgery at the University of Toronto. He is the Medical Director, CBI Health Group and Executive Director of the Canadian Spine Society in Toronto, Ontario.
Greg McIntosh, MSc, completed his Masters in Epidemiology from the University of Toronto's Faculty of Medicine. He is currently the Director of Clinical Research for CBI Health Group and research consultant to the Canadian Spine Society.

Abstract
This article highlights the myths and misunderstandings surrounding the straight leg raise (SLR) test for sciatica. Unfortunately, neither intra- nor inter-observer reliability of the passive SLR test has ever been agreed upon. In addition, there is poor consensus about what constitutes a positive SLR test in terms of pain location, leg elevation limitation or clinical significance. Until there are stricter performance standards and uniform agreement, researchers and clinicians should interpret the test with caution. We believe a true positive SLR should be the reproduction or exacerbation of the typical leg dominant pain in the affected limb at any degree of passive elevation. Those with only increased back pain or any leg pain other than that presenting as the chief complaint should be regarded as false positives.
Key Words: low back pain, straight leg raise, sciatica, irritative test.

Joseph M Lam

 et al.

Jacky Lo1, Joseph M. Lam, MD, FRCSC2
1Medical student, Department of Pediatrics, University of British Columbia, Vancouver, BC.
2Clinical Assistant Professor, Departments of Pediatrics and Dermatology, University of British Columbia, Vancouver, BC.

Abstract
Diaper dermatitis is one of the most common skin conditions seen in the pediatric population and can cause significant distress for infants and their families. While many diaper rashes can resolve with simple treatments, having a thorough understanding of different diaper lesions can help rule out more serious conditions, guide treatment and alleviate some of the caregivers' anxiety. The following review article will provide an overview of select common and uncommon diaper eruptions.
Key Words: diaper dermatitis, pediatric, diaper rash, treatment.

Curtis M. Marcoux, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada.
Dr. Pradeep Shenoy, MD, DLO, FRCS, FACS,
is the ENT service chief, Campbellton Regional Hospital, Campbellton, New Brunswick, Canada.

Abstract
Dizziness is the third most common symptom seen in patients of all age groups who present to emergency departments, outpatient clinics and physicians offices. Assessing dizziness requires a differentiation of potential causes through a comprehensive medical history and thorough physical exam. The most common causes of dizziness are peripheral vestibular disorders, however disorders of the central nervous system must be ruled out. Understanding how to distinguish between various underlying causes of vertigo is essential for the timely diagnosis and effective management of patients with this symptom. In this review, an overview of the epidemiology, etiology, presentation, diagnosis and treatment of the most common causes of vertigo will be presented, touching on some of the more rare determinants.
Key Words: Vertigo, dizziness, BPPV, vestibular neuronitis, Meniere's disease, vestibular migraine, vertebrobasilar insufficiency.

Dr.Michael Gordon Michael Gordon, MD, MSc, FRCPC, Medical Program Director, Palliative Care, Baycrest Geriatric Health Care System, Professor of Medicine, University of Toronto, Toronto, ON.

Abstract
Physicians are used to using language in very special ways. We combine the normal syntax, grammar and rules of our mother tongue along with the special clinical terms derived from Latin or Greek which are often anglicized in North America. But there are terms used in the English language that we tend to avoid because they have associated with them negative stereotypes about certain groups of individuals and over time, no one would use some of these terms in public. The term tsunami has entered the lexicon recently of terms used to describe the challenges of the aging population. Its use has entered the popular media and amongst policy makers. Physicians must be attuned to the negative stereotype associated with the use of this term to describe the older patients that we collectively care for.
Key Words:Language and negative stereotypes, media use of terms, stigmatizing the elderly with words.

Jordan Isenberg

 et al.

Jordan Isenberg,1 Tessa Weinberg,2 Nowell Solish,3
1McGill University, Faculty of Medicine, Montreal, Quebec; 2The Royal College of Surgeons in Ireland, Faculty of Medicine, Dublin, Ireland;
3University of Toronto, Department of Dermatology, Toronto, Ontario.


Abstract
Merkel cell carcinoma (MCC) is a rare and aggressive cutaneous malignancy. It is seen most frequently in those over 60 years old and in Caucasian males. It usually presents as an asymptomatic rapidly growing violatious nodule on a sun exposed area. The mainstay of treatment is surgical by standard wide local excision or MOHs chemosurgery. Radiation is added frequently for local control. The only factor significantly associated with overall survival is the stage of disease at presentation. This stresses the importance of early diagnosis and treatment.
Key Words: Merkel cell carcinoma, wide local excision, MOHs chemosurgery, adjuvant radiotherapy, review, case.

This article is being developed and will be posted soon. Thank you.

1,2Darren M. Roffey PhD; 1Simon Dagenais DC, PhD, MSc; 3Ted Findlay DO, CCFP; 4,5Travis E. Marion MD, MSc; 6Greg McIntosh MSc; 7,8Mohammed F. Shamji MD, PhD, FRCSC; 1,2,4,5Eugene K. Wai MD, MSc, FRCSC

1University of Ottawa Spine Program, The Ottawa Hospital, Ottawa, ON, 2Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON,

3
Department of Family Medicine, University of Calgary, Calgary, AB, 4Division of Orthopaedic Surgery, The Ottawa Hospital, Ottawa, ON, 5Department of Surgery, Faculty of Medicine, University of Ottawa, ON, 6CBI Health Group, Toronto, ON, 7Division of Neurosurgery, Toronto Western Hospital, Toronto, ON,

8Department of Surgery, University of Toronto, Toronto, ON.

Abstract

Obesity and low back pain are equally complex medical conditions with multi-factorial etiologies. Their clinical practice guidelines both include recommendations for screening and examination that can be easily implemented. There is sufficient information to compile a framework for the primary care provider, partnering with the patient and appropriate specialists, to manage obesity and low back pain in a structured fashion. Weight loss and exercise are paramount and should be recommended as the first options. Cognitive behavioural therapy, pharmacological treatment and bariatric surgery may then be implemented sequentially depending upon the effectiveness of the initial interventions.

Key Words: Obesity, low back pain, exercise, nutrition, cognitive behavioural therapy, bariatric surgery, weight loss, pharmacological, evidence-based guideline.

1,2Darren M. Roffey PhD; 1Simon Dagenais DC, PhD, MSc; 3Ted Findlay DO, CCFP; 4,5Travis E. Marion MD, MSc; 6Greg McIntosh MSc; 7,8Mohammed F. Shamji MD, PhD, FRCSC; 1,2,4,5Eugene K. Wai MD, MSc, FRCSC

1University of Ottawa Spine Program, The Ottawa Hospital, Ottawa, ON, 2Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON,

3
Department of Family Medicine, University of Calgary, Calgary, AB, 4Division of Orthopaedic Surgery, The Ottawa Hospital, Ottawa, ON, 5Department of Surgery, Faculty of Medicine, University of Ottawa, ON, 6CBI Health Group, Toronto, ON, 7Division of Neurosurgery, Toronto Western Hospital, Toronto, ON,

8Department of Surgery, University of Toronto, Toronto, ON.

Abstract

Obesity and low back pain are equally complex medical conditions with multi-factorial etiologies. Their clinical practice guidelines both include recommendations for screening and examination that can be easily implemented. There is sufficient information to compile a framework for the primary care provider, partnering with the patient and appropriate specialists, to manage obesity and low back pain in a structured fashion. Weight loss and exercise are paramount and should be recommended as the first options. Cognitive behavioural therapy, pharmacological treatment and bariatric surgery may then be implemented sequentially depending upon the effectiveness of the initial interventions.

Key Words: Obesity, low back pain, exercise, nutrition, cognitive behavioural therapy, bariatric surgery, weight loss, pharmacological, evidence-based guideline.

Dr. Pradeep Shenoy, MD, DLO, FRCS, FACS, is the ENT service chief, Campbellton Regional Hospital, Campbellton, New Brunswick, Canada.
Dr. Paul Cortin, MD, Opthalmology Service Chief, Campbellton Regional Hospital, New Brunswick, Campbellton, Canada.
Dr. O. Oni, MD, Paediatrician, Campbellton Regional Hospital, New Brunswick, Campbellton, Canada Hospital,NB,Campbellton,Canada.

Abstract
A case of congenital nasolacrimal mucocele presenting with medial canthus cystic mass and purulent eye discharge is reported. Clinical features, investigations and treatment modalities are described after reviewing the literature.
Key Words: CNDM (congenital nasolacrimal duct mucocoele), dacrocystocoele, dacryocele,
lacrimal sac cyst, amniotocele, medial canthus cystic mass, purulent conjunctivitis, surgical probing, silicone intubation, marsupialization.

Ian PUN, MD, Family Physician, Scarborough, Ontario.
OSCAR McMaster EMR user since 2010.

Abstract
As of 2014, over 75% of primary care physicians in Ontario have adopted,1 or are in the process of adopting an EMR. Those physicians who are new to using EMR will find many pitfalls, many of which are common and are preventable. I will specifically deal with the OSCAR McMASTER EMR and what issues I saw my fellow colleagues and myself experience in the Ontario context.
Key Words: Hardware, Network, OSCAR McMaster EMR, issues, scanning, lab, HL7.

1,2Darren M. Roffey PhD; 1Simon Dagenais DC, PhD, MSc; 3Ted Findlay DO, CCFP; 4,5Travis E. Marion MD, MSc; 6Greg McIntosh MSc; 7,8Mohammed F. Shamji MD, PhD, FRCSC; 1,2,4,5Eugene K. Wai MD, MSc, FRCSC

1University of Ottawa Spine Program, The Ottawa Hospital, Ottawa, ON, 2Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON,

3
Department of Family Medicine, University of Calgary, Calgary, AB, 4Division of Orthopaedic Surgery, The Ottawa Hospital, Ottawa, ON, 5Department of Surgery, Faculty of Medicine, University of Ottawa, ON, 6CBI Health Group, Toronto, ON, 7Division of Neurosurgery, Toronto Western Hospital, Toronto, ON,

8Department of Surgery, University of Toronto, Toronto, ON.

Abstract

Recognizing that the increasing incidence of obesity coincides with the rising prevalence of LBP, there is growing interest in establishing the relationship between over-weight and back pain. It is likely that any association is multi-factorial and that the connection is not as mechanistically simple as previously believed. Systemic inflammation associated with obesity may be an important contributor. Proposed treatment options vary from cognitive behavioural therapy to bariatric surgery with none yet fully proven. Despite the ambiguity, it appears prudent for primary care providers treating obese patients with LBP to recommend weight loss and exercise.

Key Words: Obesity, low back pain, inflammation, intervertebral disc, multi-factorial, causality, association.

1,2Darren M. Roffey PhD; 1Simon Dagenais DC, PhD, MSc; 3Ted Findlay DO, CCFP; 4,5Travis E. Marion MD, MSc; 6Greg McIntosh MSc; 7,8Mohammed F. Shamji MD, PhD, FRCSC; 1,2,4,5Eugene K. Wai MD, MSc, FRCSC

1University of Ottawa Spine Program, The Ottawa Hospital, Ottawa, ON, 2Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON,

3
Department of Family Medicine, University of Calgary, Calgary, AB, 4Division of Orthopaedic Surgery, The Ottawa Hospital, Ottawa, ON, 5Department of Surgery, Faculty of Medicine, University of Ottawa, ON, 6CBI Health Group, Toronto, ON, 7Division of Neurosurgery, Toronto Western Hospital, Toronto, ON,

8Department of Surgery, University of Toronto, Toronto, ON.

Abstract

Recognizing that the increasing incidence of obesity coincides with the rising prevalence of LBP, there is growing interest in establishing the relationship between over-weight and back pain. It is likely that any association is multi-factorial and that the connection is not as mechanistically simple as previously believed. Systemic inflammation associated with obesity may be an important contributor. Proposed treatment options vary from cognitive behavioural therapy to bariatric surgery with none yet fully proven. Despite the ambiguity, it appears prudent for primary care providers treating obese patients with LBP to recommend weight loss and exercise.

Key Words: Obesity, low back pain, inflammation, intervertebral disc, multi-factorial, causality, association.

Dr.Michael Gordon Michael Gordon, MD, MSc, FRCPC, Medical Program Director, Palliative Care, Baycrest Geriatric Health Care System, Professor of Medicine, University of Toronto, Toronto, ON.

Abstract
The process of prescribing medications, explaining the risks and benefits has classically been the role and responsibility of physicians with support from other health care providers such as pharmacists. In the modern age with the phenomenal expansion of the digital world, the world of the internet has become a major player. It is common for physicians to have to contend with and integrate into their practice the common phenomenon of family members looking at the internet and other sources for information about medications proposed for their loved ones.
Key Words: internet, medications, information, responsibility.

Francesca Cheung, MD CCFP, is a family physician with a special interest in dermatology. She received the Diploma in Practical Dermatology from the Department of Dermatology at Cardiff University in Wales, UK. She is practising at the Lynde Centre for Dermatology in Markham, Ontario and works closely with Dr. Charles Lynde, MD FRCPC, an experienced dermatologist. In addition to providing direct patient care, she acts as a sub-investigator in multiple clinical studies involving psoriasis, onychomycosis, and acne.

Abstract
Mammary Paget disease (PD) is a less common form of breast cancer which involves the nipple-areola complex and occurs almost exclusively in females. Erythema, skin thickening, pruritus, burning sensation, inversion of the nipple, ulceration, serosanguineous nipple discharge are common clinical symptoms. Approximately 1-4% of female breast carcinoma are associated with PD of the nipple-areola complex. A biopsy including the dermal and subcutaneous tissue should be performed on all suspicious lesions of the nipple-areola complex for accurate diagnosis. The first line treatment of mammary PD is mastectomy (radical or modified) and lymph node clearance for patients with a palpable mass and underlying invasive breast carcinoma. The prognosis of mammary PD is determined by the disease stage and is similar to that of other types of breast cancer.
Key Words: Mammary Paget disease, breast cancer, nipple-areola complex, metastasis.

Ted Findlay

 et al.

Dr. Ted Findlay, DO, CCFP, Clinical Assistant Professor, Department of Family Medicine, University of Calgary, Calgary, Alberta.

Mohammed F. Shamji, MD, PhD, FRCSC, Division of Neurosurgery, Toronto Western Hospital, Department of Surgery, University of Toronto, Toronto, Ontario, Canada.

Abstract
Low back pain is one of the most common conditions for which patients seek medical attention. It can be managed with lifestyle modification, or less commonly medical and surgical intervention. Appropriate selection among various pharmacological options mandates an understanding of the underlying symptomatology and the over-riding treatment plan and objectives. The range of potential medications is substantial: over-the-counter analgesics include acetaminophen and non-steroidal anti-inflammatory drugs, muscle relaxants, and weak opioid combinations including codeine or tramadol. More potent versions of many of the same components are available on prescription, commonly employing stronger opioids either singly or in a combination analgesic. When the pain involves either chronic or neuropathic features, other classes of medications, including anti-epileptic drugs and anti-depressants, may be appropriate.
Key Words: low back pain, acute, chronic, neuropathic pain, nociceptive pain, medications.

Ted Findlay

 et al.

Dr. Ted Findlay, DO, CCFP, Clinical Assistant Professor, Department of Family Medicine, University of Calgary, Calgary, Alberta.

Mohammed F. Shamji, MD, PhD, FRCSC, Division of Neurosurgery, Toronto Western Hospital, Department of Surgery, University of Toronto, Toronto, Ontario, Canada.

Abstract
Low back pain is one of the most common conditions for which patients seek medical attention. It can be managed with lifestyle modification, or less commonly medical and surgical intervention. Appropriate selection among various pharmacological options mandates an understanding of the underlying symptomatology and the over-riding treatment plan and objectives. The range of potential medications is substantial: over-the-counter analgesics include acetaminophen and non-steroidal anti-inflammatory drugs, muscle relaxants, and weak opioid combinations including codeine or tramadol. More potent versions of many of the same components are available on prescription, commonly employing stronger opioids either singly or in a combination analgesic. When the pain involves either chronic or neuropathic features, other classes of medications, including anti-epileptic drugs and anti-depressants, may be appropriate.
Key Words: low back pain, acute, chronic, neuropathic pain, nociceptive pain, medications.

Ian PUN, MD, Family Physician, Scarborough, Ontario.

Abstract
Although many doctors have embraced and modernized their practices with a the advent of an EMR (Electronic Medical Record) system, there still a remaining majority who are hesitant to convert to a computerized recording keeping system fearing change and hassle. I have listed a few brief points urging doctors to change to a more efficient system that saves time and space which will ultimately improve patient care. In future articles, I will go into more detail of specific usages of EMR, specifically the open-source OSCAR McMaster EMR. I will also point of the issues of maintaining an EMR.
Key Words: OSCAR McMaster EMR, computerized medical records, electronic prescription, health information technology.

Dr. Pradeep Shenoy, MD, DLO, FRCS, FACS, is the ENT service chief, Campbellton Regional Hospital, Campbellton, New Brunswick, Canada.

Abstract
A case of pyogenic granuloma of gingiva is presented. Aetiology factors, clinical presentations and different treatment modalities are discussed after reviewing the literature.
Key Words: Pyogenic granuloma, Gingival hyperplasia, Peripheral giant cell granuloma, peripheral ossifying fibroma, lobular capillary haemangioma.

Dr.Michael Gordon Michael Gordon, MD, MSc, FRCPC, Medical Program Director, Palliative Care, Baycrest Geriatric Health Care System, Professor of Medicine, University of Toronto, Toronto, ON.

Abstract
Diabetes Mellitus is very prevalent in the older population. It is one of the important causes of vascular problems which may play a role in the development of dementia, especially of the mixed variety. There has been much progress in the potential medications that can help promote successful glucose control and address the other metabolic correlates of Type 2 diabetes mellitus. Sulfonylureas should be used rarely and very carefully in older especially frail individuals because of their inherent risks. Getting physicians to change their prescribing practices in this frail elderly diabetic population is an important challenge to educators and drug program administrators.
Key Words: diabetes mellitus, sulfonylureas, diabetic management, treatment.

Francesca Cheung, MD CCFP, is a family physician with a special interest in dermatology. She received the Diploma in Practical Dermatology from the Department of Dermatology at Cardiff University in Wales, UK. She is practising at the Lynde Centre for Dermatology in Markham, Ontario and works closely with Dr. Charles Lynde, MD FRCPC, an experienced dermatologist. In addition to providing direct patient care, she acts as a sub-investigator in multiple clinical studies involving psoriasis, onychomycosis, and acne.

Abstract
Herpes simplex viruses (HSVs) are DNA viruses that present as vesicles in clusters on an erythematous base. Infection occurs when close contact between an individual without antibodies against the virus and a person shedding the virus takes place. Most HSV infections are self-limited. Lesions tend to reappear at or near the same location of the initial site of infection. Systemic symptoms such as fever, malaise and acute toxicity may appear, especially in primary infection. A viral culture from the skin vesicles can identify up to 80 to 90% of untreated infection early in the course. Antiviral treatments aim at shortening the disease course and preventing viral dissemination and transmission. Treatments are most effective when they are administered at the first sign of symptom onset.