[Arguments against pressure-lowering treatment of ocular hypertension. Prophylactic treatment is unnecessary].

The main argument against a pressure-lowering treatment for patients with ocular hypertension (OHT) is the principle of "first do no harm". The imprecision of intraocular pressure (IOP) measurements and the fact that increased IOP is only a risk factor for glaucoma raise major doubts on a clinical definition of OHT. The use of IOP-lowering treatment in the absence of functional or morphological glaucomatous changes should only be initiated if the IOP is very high (>32 mmHg). If the IOP is between 21 and 32 mmHg the glaucoma conversion risk of the individual patient should be estimated. The risk factors as proven in major prospective trials (OHTS/EGPS) should be assessed using the risk calculator. Only patients with a high risk (>13%) of conversion profit from prophylactic IOP-lowering treatment. For all patients with intermediate or low risk of conversion the potential side-effects (local and systemic) of the treatment outweigh the possible benefit, so that the principle of "watchful waiting" is the best for patients with OHT. If morphological or functional progression is observed IOP-lowering treatment should be started immediately.