There are three different types of nasal sprays used for allergy relief: corticosteroids, antihistamines, and decongestants. If you need relief, you would work with your ob-gyn to make sure one of these medications is right for you, especially the decongestants (the only group found over the counter).
Examples of corticosteroid nasal sprays include fluticasone (Flonase), mometasone (Nasonex), budesonide (Rhinocort Aqua), flunisolide (Nasarel), triamcinolone (Nasacort AQ), and beclomethasone (Beconase AQ). Side effects can include unpleasant smell or taste, nasal irritation, and nosebleeds. These medications are much less likely to cause any side effects than are oral corticosteroids.
Prescription antihistamine nasal sprays include azelastine (Astelin, Astepro) and olopatadine (Patanase). Side effects of antihistamine nasal spray may include bitter taste, dizziness, drowsiness or fatigue, dry mouth, headache, nasal burning, nosebleed, nausea, runny nose, sore throat, and sneezing.
Examples of nasal decongestant sprays include phenylephrine (Neo-Synephrine, others) and oxymetazoline (Afrin, others). Nasal decongestants can cause dryness, burning, or stinging inside the nose, runny nose, and sneezing. Taking too much of a nasal decongestant can cause irritability, fast or irregular heartbeat, dizziness, insomnia, headaches, anxiety, tremors, and increased blood pressure. Don't use a decongestant nasal spray for more than a week or so, or you may develop severe congestion as soon as you stop taking it (rebound congestion).