Fluticasone and salmeterol inhaler (Seretide): uses and cautions

Seretide Evohaler is the best-known brand in this group. Each puff delivers salmeterol xinafoate and fluticasone propionate. The steroid dampens inflammation inside the airways over days and weeks, while salmeterol relaxes the airway muscle for many hours, so the two cover different parts of the problem. The NHS notes that fluticasone is also found in other combination inhalers, including Flutiform, Relvar and Trelegy, which are separate products with their own leaflets.

Product information for Seretide lists three fluticasone strengths per puff, with salmeterol fixed at 25 micrograms, so prescribers can match the steroid dose to how severe asthma is. The lowest strength is not considered suitable for severe asthma.

The licence is for the regular treatment of asthma where a combination is appropriate: people not adequately controlled on an inhaled steroid plus a short-acting reliever, or people already well controlled on both an inhaled steroid and a long-acting bronchodilator. The product information adds that inhaled steroids on their own remain the first choice for most people and that Seretide is not meant for the first management of mild asthma.

A prescriber should reassess regularly so that the strength remains the lowest that keeps control. Where symptoms stay controlled on the lowest strength twice a day, the next step may be a trial of the steroid alone, or in some cases once-daily dosing if the prescriber judges that adequate.

The product information gives two inhalations twice daily as the pattern for adults and adolescents aged 12 and over, and a single strength for children from 4 years. Your own strength and number of puffs come from your prescriber and your inhaler leaflet. Children under 12 may struggle to time the puff with the breath, and a spacer is recommended when that is a problem; changing to a different make of spacer can alter the dose reaching the lungs, so the dose is re-checked after any change.

The device has a dose counter. Test-fire it as the leaflet describes before first use, hold it upright, breathe out, start breathing in slowly and then press, hold your breath for as long as is comfortable and wait about half a minute before a second puff. Rinse your mouth with water and spit, or brush your teeth, after each dose. Plan a replacement when the counter reads 020 and replace it at 000. Clean the mouthpiece and casing with a dry cloth at least weekly and never put the metal canister in water.

The only listed contraindication is hypersensitivity to the ingredients. The product information advises caution in people with active or past tuberculosis or other chest infections, severe heart disease or rhythm problems, diabetes, an overactive thyroid, and low potassium or a tendency to it. It also says treatment should not be started during a flare or while asthma is rapidly worsening.

Sudden worsening of asthma is described as potentially life-threatening. A growing need for a reliever, or a poorer response to it, signals deteriorating control and should lead to review.

The product information lists headache as very common and thrush of the mouth and throat, hoarseness, throat irritation, sinusitis and low potassium among the common effects. Pneumonia and bronchitis are also reported as common in some groups. Tremor, palpitations, a fast heartbeat, anxiety, sleep disturbance and cataract are uncommon. Rare effects include paradoxical bronchospasm, an immediate worsening of wheeze after a dose, which needs a rapid-acting bronchodilator and stopping the inhaler, and effects of long-term steroid exposure such as Cushing's features, adrenal suppression, reduced bone density and slower growth in children.

Allergic reactions, including swelling of the face or throat, are possible but rare. Wheeze after a dose, collapse, severe breathlessness, or swelling of the lips, tongue or throat calls for 999. Report suspected side effects through the Yellow Card scheme.

Beta blockers can weaken salmeterol and are generally avoided in asthma unless there is a compelling reason. Water tablets, steroids and xanthine medicines such as theophylline can compound low potassium. Strong inhibitors of the CYP3A4 enzyme raise exposure to both drugs; the entry names ritonavir, ketoconazole, itraconazole, cobicistat products and telithromycin, with erythromycin a milder example, and advises avoiding the combination unless the benefit outweighs the risk.

For pregnancy, the product information says data on over 1,000 pregnancy outcomes show no malformation or newborn toxicity linked to Seretide, but use should be considered only if the expected benefit outweighs any risk and the lowest effective steroid dose should be used. It is unknown whether either drug passes into breast milk, so benefit and risk are weighed with the prescriber. Driving is not normally affected.

The entry advises that treatment should not be stopped abruptly because asthma can flare, and that any reduction is done under medical supervision. Someone who has switched from steroid tablets may keep a reduced adrenal reserve for a considerable time and needs extra care. If you ever need an operation, emergency care or have a serious infection, tell the team you use an inhaled steroid.