In a primary healthcare facility, there are certain 'rules of thumb' that can be recommended for the diagnosis and treatment of conjunctivitis. The type of discharge is a crucial factor in the differential diagnosis and can also be a clue towards the management in primary care. It is important to identify whether the conjunctivitis is an isolated case or part of another disease, and if it is acute or chronic, and I would suggest taking a smear or culture sample whenever possible. When the aetiology is not clear, I would try antibiotics. If the patient is allergic, and an allergic conjunctivitis is suspected, the best management today is to use mast cell stabilisers, and combine these with conservative measures of frequent washings, and compresses. If the aetiology remains doubtful, or if there is no obvious improvement using these treatments, the patient should be re-evaluated and/or referred to an ophthalmologist or specialist eye centre. The use of corticosteroids for conjunctivitis should certainly be avoided in primary healthcare. Conjunctivitis is often self-limited and the drug-induced consequences of improper management can be far more devastating than the disease itself.