Drug treatment

The management of allergic rhinitis is summarised in Figure 1. Many sufferers will need more than one treatment. Ideally, treatments should be increased stepwise and then stepped down once the condition resolves. The actions and comparative efficacy of the available agents are shown in Tables 1 and 2.

For mild, intermittent AR the first step is a non-sedating oral antihistamine and/or a decongestant for short-term use. Intranasal azelastine has a faster onset of action and is more effective than oral preparations. However, intranasal azelastine is a POM. It also has a bitter taste if it trickles into the throat.

For mild-to-moderate intermittent or mild persistent symptoms, a non-sedating oral antihistamine and/or decongestant for short-term use or intranasal corticosteroid or intranasal chromone are all options. In practice, the most acceptable treatment at this stage is likely to be an intranasal corticosteroid (ICS), which reduces nasal congestion.

Onset of action is six to eight hours after the first dose but it can take up to two weeks for the maximal effect, so hayfever sufferers should be advised to start treatment two weeks before the start of the allergen season. All ICS have similar clinical efficacy, but bioavailability varies considerably.

Systemic absorption is negligible with mometasone furoate and fluticasone propionate in particular, and these preparations are favoured for children. Note that a new POM to P switch has recently been launched, Clarinaze Allergy Control (mometasone furoate 0.05%; prescribed as Nasonex). The OTC nasal spray is suitable for adults aged 18 years and over.

An intranasal chromone such as sodium cromoglicate can be used 'as needed' if antihistamines are contraindicated or not tolerated. If conjunctivitis is a problem, an intra-ocular chromone can be recommended for regular prophylactic use or combination decongestant/antihistamine eyedrops (Otrivine Antistin) used. Wrap-around sunglasses can also be helpful.

Moderate-to-severe, persistent symptoms of AR warrant referral to a GP. Such patients may require a more detailed medical assessment and prescribed treatment with an intranasal antihistamine or leukotriene antagonist.