E.R. Blay
I have met this kind of problem, and what needs to be considered is allergy to drug excipients. In other words the fraction of a drug preparation that is used to flavour, coat , provide bulk etc for the final tablet ,liquid preparation or capsule. One answer is to use specially formulated preparations that deal with this problem. Pharmacists know of this. There is a book 'Drug Excipients'which is published by the Pharmaceutical press,UK. I first met this problem when a patient developed allergy to a potassium chloride tablet. This was caused by the manufacturers using saccharine when cyclamates were banned as the sweetening agent. In other cases I even asked the pharmacist to avoid passing tablets through a tablet counting machine to avoid trace contamination of one tablet by those that had previously gone through the machine. A nano-gramme of the offending substance can cause a reaction.(1/100,000000 of a gramme) I have seen this with a test dose of lidoflazine. Pharmacists can make up special formulations in inert vehicles or bases. The injection or parenteral prepararation is often the pure anti-biotic and can just be dissolved or suspended in water or even mixed with food. Professor Rea has written 4 volumes on chemical sensitivity and Dr Richard Mackarness wrote a book, 'Chemical Victims' Clinical Ecologists are usually aware of this problem. Hydroxyl groups and the amino group seem to cause problems. It links up t0 protein binding of drugs and the topic of haptens. There are possible answers through de-sensitization .Best wishes