Can I take 18 and 40 together?
Drug interaction guide
Originally published 14 Mar 2026
Meets Patient’s editorial guidelines
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There is no known interaction between these two substances. However, it is important to note that '18' and '40' are not recognised names of medications, supplements, or substances. If these numbers refer to specific dosages of different drugs, the names of those drugs are required to provide an accurate safety assessment.
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Why this happens
No pharmacological interaction can be identified without the names of the substances involved.
What you should do
Back to contentsPlease provide the names of the medications or supplements you are referring to. Always consult with a pharmacist or doctor before combining new treatments to ensure they are safe for your specific health needs.
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Using other medicines
Back to contentsTaking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.
Disclaimer
This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.
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There is no direct interaction between empagliflozin and mirtazapine. However, both medications can occasionally cause a drop in blood pressure when you stand up (postural hypotension). Taking them together might slightly increase the risk of feeling dizzy or light-headed.
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Taking sildenafil (Viagra) and amlodipine together can cause your blood pressure to drop lower than intended. This may make you feel dizzy, lightheaded, faint, or cause a headache.
Article history
The information on this page is written and peer reviewed by qualified clinicians.
14 Mar 2026 | Originally published
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