Pain Pathophysiology Overview

Receptors involved in pain modulation: opioid receptors alpha-2 adrenergic receptors voltage-gated calcium channels NMDA receptors Chemical mediators (sensitize neurons to pain): substance P prostaglandins bradykinin glutamate Neurotransmitters (facilitate pain modulation): norepinephrine serotonin GABA

Overview of Types of Pain

acute pain: < 1 month in duration chronic pain:  > 6 months in duration can arise from nociceptive and/or neuropathic origins Nociceptive pain:  experienced in the presence of an injury or trauma.  Can be described as sharp, dull, or achy and may either be localized or diffuse. examples include: osteoarthritis and pancreatitis. Neuropathic pain: pain … Continue reading

Migraine Headache

Migraine Headache Most common in women by the age of 35 Believed to be a neurovascular HA We use prophylactic agents (vasodilators like BBs) to prevent constriction but for acute attacks we use vasoconstrictors (like triptans) to dilate other arteries in the scalp & neck Migraine Symptoms: Prodrome:  indicates a migraine is imminent.  May be … Continue reading

Tension Headache

Tension Headache Most common type of HA More common in women usually by age 20 Acute more common than chronic Pain originates from myofascial tissues, exacerbated by physical/mental stress Symptoms:  pain is mild-moderate, band-like, dull, non-pulsating & bilateral               often coexists with depression Muscle tension is common:  patients have difficulty relaxing on command, have restless movements … Continue reading

Cluster Headache

Cluster headache More common in men usually in 3rd decade of life (women more commonly get it in their 60s) Comes in a cluster lasting 2 weeks to 3 months Patients will typically go 2 years w/o a HA  (most pts experience episodic) Symptoms:  suicide headache, usually occurs at night, pain is unilateral, comes on … Continue reading


Pathophysiology of uric acid and how its disregulation can lead to hyperuricemia and different gout diseases Uric acid is a waste product that is produced as the final product of purine metabolism & is excreted via the urine (2/3) & GI (1/3) Hyperuricemia occurs when there’s an imbalance between the production & excretion Overproduction of … Continue reading


Clinical presentation of osteoarthritis (OA) Various degrees of inflammation but NO systemic effects Mainly affects weight bearing joints (causes pain, limits range of motion, disability & QOL) Incidence & severity increase with age (more commonly affects women) Primary osteoarthritis (idiopathic) is the most common type Localized = 1-2 sites Generalized = 3+ sites Erosive = … Continue reading