Adverse Reactions & Pharmacovigilance

Adverse Event AE

TRAdvers Olay
Also known as:Adverse experience

Any untoward medical occurrence in a patient or clinical-trial subject given a medicinal product, whether or not it is considered causally related to the treatment.

In depth

An adverse event can be any unfavourable and unintended sign (including an abnormal laboratory finding), symptom or disease temporally associated with use of a medicinal product. The concept, defined in ICH E2A and applied under Good Clinical Practice, deliberately makes no assumption about causality, so that all events are captured without selection bias.

In clinical trials, adverse events are recorded in every arm, graded for severity (e.g., mild, moderate, severe, or CTCAE grades 1–5 in oncology) and assessed for seriousness and relatedness. Events judged to have at least a reasonable possibility of a causal relationship are termed adverse reactions; true drug effects are revealed by comparing event rates between active and control arms rather than by individual reports.

Clinical pearl

A higher adverse event rate in a treatment arm is meaningful only relative to the control arm; many events in trials, including those leading to discontinuation, also occur with placebo.

TRIn Turkish

Advers Olay

Bir tıbbi ürün uygulanan hasta veya klinik araştırma katılımcısında ortaya çıkan, tedaviyle nedensellik ilişkisi olup olmadığına bakılmaksızın istenmeyen her türlü tıbbi durumdur.

Advers olay, bir tıbbi ürünün kullanımıyla zamansal olarak ilişkili, istenmeyen ve amaçlanmayan herhangi bir bulgu (anormal laboratuvar sonucu dahil), belirti veya hastalık olabilir. ICH E2A'da tanımlanan ve İyi Klinik Uygulamalar kapsamında kullanılan bu kavram, tüm olayların seçim yanlılığı olmaksızın kaydedilmesi için bilinçli olarak nedensellik varsayımında bulunmaz.

Klinik araştırmalarda advers olaylar tüm kollarda kaydedilir, şiddetine göre derecelendirilir (ör. hafif, orta, şiddetli ya da onkolojide CTCAE derece 1–5) ve ciddiyet ile ilaçla ilişki açısından değerlendirilir. İlaçla nedensellik ilişkisi en azından makul bir olasılık olarak değerlendirilen olaylar advers reaksiyon olarak adlandırılır; gerçek ilaç etkilerini tek tek bildirimler değil, etkin ve kontrol kolları arasındaki olay sıklıklarının karşılaştırılması ortaya koyar.

Tedavi kolundaki advers olay sıklığının yüksekliği ancak kontrol koluyla karşılaştırıldığında anlam taşır; tedavinin bırakılmasına yol açanlar dahil pek çok olay plaseboyla da görülür.

Diğer adları:İstenmeyen olay
Updated 24.09.2026 0 views Educational reference — verify against current sources before clinical use.

Read next

Adverse Drug ReactionAdvers İlaç Reaksiyonu

A noxious and unintended response to a medicinal product in which a causal relationship with the drug is at least a reasonable possibility.

 Serious Adverse EventCiddi Advers Olay

An adverse event that results in death, is life-threatening, requires or prolongs hospitalisation, causes persistent or significant disability, is a congenital anomaly, or is otherwise medically important.

 Good Clinical Practiceİyi Klinik Uygulamalar

An international ethical and scientific quality standard for designing, conducting, recording and reporting clinical trials, ensuring that participants' rights, safety and well-being are protected and that trial data are credible.

 Randomized Controlled TrialRandomize Kontrollü Çalışma

A prospective experimental study in which participants are allocated by chance to an intervention or a control (placebo, usual care or an active comparator) and followed up to compare outcomes.

 Nocebo EffectNosebo Etkisi

The occurrence or worsening of symptoms, including adverse effects, that results from negative expectations about a treatment rather than from its pharmacological action.

 PharmacovigilanceFarmakovijilans

The science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other medicine-related problem (WHO definition).