Yes, overusing nasal decongestant drops can sometimes cause rebound congestion and headaches. However, a severe headache paired with swelling on one side of your head is not a typical side effect and could indicate a localized sinus infection or inflammation. Since steam and menthol rubs haven't provided relief, it is very important that you stop using the drops and consult a healthcare professional promptly for an accurate diagnosis. Please avoid using over-the-counter nasal decongestants for more than three to five consecutive days.

For safe relief at eight months, try steam inhalation with plain water to soothe your dry nose, and drink warm water mixed with honey and a little ginger to ease your throat. Saline nasal drops are also highly safe and effective for dryness. Since you are in your third trimester, please consult your obstetrician before taking any commercial Ayurvedic formulations or continuing cetirizine (citrazen). Always prioritize your and your baby's safety by avoiding self-medication with complex herbal remedies right now.

The burning sensation and reduced sense of smell are likely due to the viral infection itself causing inflammation in your nasal passages, rather than the Vicks Action 500, though oral decongestants like phenylephrine can sometimes cause mild dryness. To help soothe your nose, try using a simple saline nasal spray and steam inhalation to restore moisture. This should gradually improve as your body recovers from the cold. However, if these symptoms persist past a week or worsen, please consult a healthcare professional for a gentle evaluation.

It is very common to experience this sensation, and it could be a combination of both factors. Recovering from COVID-19 two weeks ago can leave behind lingering inflammation in your deeper sinus passages, creating a persistent feeling of mucus. Additionally, frequent use of a Vicks inhaler can irritate your nasal passages or cause a rebound effect, altering how you perceive airflow. To help your nasal lining heal, try pausing the inhaler and using a gentle saline nasal spray to keep the area hydrated. This sensation is typically temporary and should improve soon. Please consult a doctor if it persists.

I am so sorry you have been dealing with this persistent dry cough for over two weeks; I know how exhausting that can be. While diphenhydramine (Benadryl) and Vicks can offer temporary comfort, they are not addressing the root cause. Since your cough has lasted more than 15 days, your best next step is to see a doctor for a proper evaluation. They can check for common causes like post-nasal drip, allergies, or acid reflux, and prescribe targeted treatments. In the meantime, try staying well-hydrated with warm fluids and using a humidifier to soothe your airways. Please take care.

Since you have completed your five-day course of ivermectin and azithromycin, you should stop taking them. For your remaining mild cough, plain steam inhalation is highly effective and gentler on your airways than adding Vicks or Karvol. You can take paracetamol as needed for discomfort, ensuring you do not exceed 3,000 mg in 24 hours. Most importantly, please consult your doctor promptly regarding your elevated blood sugar and inflammation levels, as these require close medical supervision and tailored management. Rest well, stay hydrated.