Source: Fiscella RG, Lesar
TS, Edward DP. Glaucoma. In: DiPiro, JT, Talbert RL, Yee GC, Matzke
GR, Wells BG, Posey LM. Pharmacotherapy: A Pathophysiologic Approach.
8th edition. http://accesspharmacy.com/content.aspx?aid=7998061. Accessed July 10, 2012.
- Ocular disorder leading to optic neuropathy characterized
by changes in optic nerve head (optic disk) associated with loss
of visual sensitivity and field.
- Inherited disorder, congenital, or secondary to disease,
trauma, or drugs.
- Secondary open-angle glaucoma caused by:
- Pigmentary glaucoma
- Systemic diseases
- Ocular inflammatory diseases
- Drugs (Table 1)
- Secondary glaucoma classified as:
Table 1. Drugs that May
Induce or Potentiate Increased Intraocular Pressure in Open-Angle Glaucoma |Favorite Table|Download (.pdf)
Table 1. Drugs that May
Induce or Potentiate Increased Intraocular Pressure in Open-Angle Glaucoma
Ophthalmic corticosteroids (high risk)
Vasodilators (low risk)
Cimetidine (low risk)
- Cause of optic neuropathy unknown.
intraocular pressure (IOP) historically considered to be sole cause.
- Additional contributing factors include increased susceptibility
of optic nerve to:
- Autoimmune reactions
- Other abnormal physiologic processes
- Risk of visual field loss increases with increasing IOP.
- IOP not constant and changes with:
- Blood pressure
- Forced expiration or coughing
- Neck compression
- IOP demonstrates diurnal variation with minimum pressure around
6 p.m. and maximum pressure upon awakening.
- IOP determined by balance between inflow and outflow of aqueous
- Increased by β-adrenergic
- Decreased by α2- and β-adrenergic blockers, dopamine
blockers, carbonic anhydrase inhibitors (CAIs), and adenylate cyclase
- Increased by cholinergic agents, prostaglandin
analogs, and β- and α2-adrenergic agonists.
- Second leading cause of blindness
- Incidence increases with increasing age.
- Essential to early diagnosis
- Annual eye
examinations recommended with family history of glaucoma and in
- IOP measurement and eye exams recommended every 3–5
years for those older than 50 years.
- Ocular hypertension
- Family history of
- Black race
- Severe myopia
- Presence of only one eye
- Slowly progressive and usually asymptomatic until onset
of substantial visual field loss. Central visual acuity
maintained, even in late stages.
- No symptoms until substantial visual field loss occurs.
- Disk changes and visual field loss
- IOP can be normal or elevated (>21 mm Hg [2.8 kPa]).
Means of Confirmation
- Diagnosis confirmed by presence of characteristic optic
disk changes and visual field loss, with or without increased IOP.
- Normal tension glaucoma refers to disk changes, visual
field loss, and IOP <21 mm Hg (2.8 kPa).
- Ocular hypertension refers to IOP >21 mm Hg (2.8 kPa) without
disk changes or visual field loss.
- Ophthalmoscopic exam
- Measurement of IOP
- Reduction of IOP to stop optic nerve damage and preserve