Start hay fever treatment before the season
Steroid nasal sprays take two weeks to reach full effect, so the best time to start hay fever treatment is before your pollen season — here is when.
The best time to start hay fever treatment is two to four weeks before your pollen season begins — mid-March if tree pollen is your trigger, mid-to-late April for the grass pollen that drives most UK hay fever. Steroid nasal sprays, the most effective everyday treatment, take up to two weeks of daily use to reach full strength, so a spray started when your eyes are already streaming spends its first fortnight catching up. Starting ahead of the season, then continuing daily through it, is the single highest-value change most people with hay fever can make.
Why starting early works so much better
Two reasons. The first is pharmacology: steroid nasal sprays calm the immune lining of the nose gradually — noticeable benefit takes days, full effect up to two weeks — so they need a head start. The second is a quirk of allergy called priming: once your nose has been inflamed by a few days of pollen exposure, it reacts to far smaller amounts than it did at the season's start. Protect the lining before the first serious pollen days and the reaction threshold stays high all season; let inflammation establish itself and every later day is harder work. People who "only get it badly in June" are often paying for an untreated April and May.
Know your pollen calendar
- Tree pollen — late February to mid-June. Birch is the big one for most tree-allergic people, peaking around April; hazel and alder start earlier.
- Grass pollen — mid-May to July, with twin peaks in early June and early July. Around 95% of UK hay fever involves grass.
- Weed pollen — late June to September (nettle, dock, mugwort).
- Mould spores — autumn, and a cause of hay-fever-like symptoms outside pollen season.
Match your worst weeks against this calendar and your start date falls out of it: symptoms every June mean beginning treatment in late April or early May.
What to start, and when
A steroid nasal spray (beclometasone, fluticasone or mometasone, all available from pharmacies) is the anchor: start it two weeks before your season and use it every day, not just on bad days — it prevents inflammation rather than rescuing you from it. A non-drowsy antihistamine (cetirizine, loratadine or fexofenadine) joins in when the season starts; taken daily it works better than chasing symptoms after they appear. Antihistamine or sodium cromoglicate eye drops earn their place when itchy eyes dominate despite the spray. Skip older sedating antihistamines like chlorphenamine for daily use — the drowsiness affects driving and concentration even when you cannot feel it.
Spray technique decides half the result
Most "the spray did nothing" stories are technique stories. Shake the bottle, tilt your head slightly forward, use your right hand for your left nostril and vice versa, and aim towards the outer wall of the nose — away from the middle partition. Don't sniff hard afterwards; a gentle breath in is enough, because a hard sniff sends the dose straight down your throat. Used like this, a steroid spray outperforms any tablet for a blocked nose.
Caught out mid-season?
Start the spray anyway — it still works, it just needs its fortnight, so add a daily antihistamine immediately for cover while it builds. On heavy pollen days: check the forecast, keep bedroom windows shut in the early morning and evening when pollen falls, wear wraparound sunglasses outdoors, rinse your hair before bed, and change out of clothes worn outside. A smear of barrier balm around the nostrils traps a surprising amount of pollen before it lands.
When pharmacy treatment is not enough
If a correctly used daily spray plus a daily antihistamine still leaves you dreading the season — sleep wrecked, exams or work suffering — that is the point for a clinical review rather than more of the same. Prescription options include stronger antihistamines, combination sprays that pair an antihistamine with the steroid in one device, and, for a small group with severe proven grass allergy, immunotherapy started months before the season under specialist care. You can check your eligibility for hay fever treatment online and a UK clinician will review what you have already tried.
Frequently asked questions
Which antihistamine is strongest?
They are closer than the packaging suggests, and responses are individual. Fexofenadine causes the least drowsiness of the main non-drowsy options; if one antihistamine seems to fade for you over the season, switching to another is reasonable.
Are steroid nasal sprays safe to use all season?
Yes at pharmacy doses — the amount absorbed into the body is tiny compared with steroid tablets. Nosebleeds or stinging usually mean the spray is hitting the middle partition of the nose; adjusting the angle fixes it.
Does local honey prevent hay fever?
No good evidence supports it. The pollen in honey comes from flowers, carried by insects — hay fever is caused by wind-borne grass and tree pollen, which barely features in honey.
Can hay fever start in adulthood?
Yes, and commonly — a first bad season in your twenties, thirties or forties is well recognised. Treat it properly from the start rather than waiting a year to see whether it returns; it usually does. Moving house or region can set it off too — a different pollen mix takes a season or two to sensitise your immune system, which is why a first-ever spring of sneezing after relocating is such a common story. The approach is the same at any age of onset: start before your season, and stay consistent through it.
Related reading
More clinically reviewed articles: all health guides.