###Human: I have severe nasal congestion. Can I use Pseudoephedrine and Otrivin together? ###Assistant: Hello. With the details provided, I understand that you are a 22 year old female suffering from cold or sinus infection causing nasal blockage. Currently you are taking Sudafed tablets and Otrivin plus nasal spray. Presuming that the Sudafed tablets you use contains only Pseudoephedrine, I would say that it is perfectly alright to take Sudafed and Otrivin plus together. Both have similar actions and will act to decrease the nasal congestion and relieve the blocked nose. Pseudoephedrine tablets will get absorbed into blood and act systemically. However otrivin nasal spray being sprayed into nasal mucosa will act only locally with very little systemic absorption through the blood vessels. The two compounds have slightly different mechanisms of action as well and use different set of receptors and messengers to bring about their action. You need to worry about their combined action only if you suffer from hypertension or elevated blood pressure. Otherwise till you meet your GP it is fine to take both together. However, do not take Pseudoephedrine more than twice a day in normal strength. If it is maximal strength tablet then take not more than once a day unless advised by your GP. However follow these general instructions till your GP makes a decisive diagnosis and institutes the most appropriate treatment for you. Consult an allergy specialist online for further follow up -->