Started Minoxidil 5% 4 weeks ago, last week I experienced irritation and itching. If I discontinue use will I lose more hair?

Because you have started using minoxidil just for four weeks the risk of aggravation of hair loss after discontinuing the minoxidil is not high, about 5 percent of individuals have different forms of hypersensitivity to minoxidil which needs to discontinue or changed to %2 after resolving the issue

At week 4, the risk is low but not zero. However, if you find that you can’t use minoxidil then stopping might indeed be the best option. You’ll want to have a good discussion with you health care team. There could be a bit of temporary shedding but in 95% of people this will settle down again in 8-13 weeks and you’ll be back right where you started. It’s important to understand there is no rule here as to what will happen only estimates on the likelihood of various scenarios. The most likely scenario is that stopping at this point will be associated with minimal disruption. To more important issues in my mind are two fold: 1) why exactly are you getting these symptoms and what can be done? and 2) is the next step and alternative for treatment acceptable or unacceptable to you? If the minoxidil is triggering a bit of seborrheic dermatitis then you and your doctors might add more frequent shampooing or might add a dandruff shampoo to the plan. You might also consider whether changing formulations (from solution to foam or from 5% to 2% might be a good idea). Stopping altogether might be ill advised if the remedy is simple. If you stop minoxidil, what are the options on the table? How well do they work? What is the cost? What is the safety? Minoxidil is quite good from the perspective of safety, affordability, feasibility and effectiveness so be sure to learn absolutely everything about the alternatives.