Don't. Making such a drug at home and then ingesting it is risky. 1. You have no guarantee as to the purity of the drug. It may contain contaminants that could harm you. Your house is not a clean environment; the 'clean room' used by manufacturers is not accomplished by wiping down the counters in a kitchen. Since you do not have the facilities to test the purity of the drug, it will certainly not be of the same quality as manufactured penicillin. 2. You will not know what dose you will be taking. Taking too much or too little of any broad-spectrum antibiotic is not recommended. Too little will not be effective and will contribute to the development of more resistant strains of bacteria. This is also why you should always finish any series of prescribed antibiotics. Too much will produce undesireable side effects. Some of the excess is excreted, where it eventually finds its way into the water table. It also contributes to the development of resistant bacteria. This is why penicillin is not prescribed as frequently today as it was in the past. 3. Penecillin is ineffective against many strains of bacteria and not very effective against others. Using the wrong antibiotic will not cure the infection, but will, once again, lead to the development of more resistant strains of bacteria. 4. You do not know how your drug will interact with any other drugs you are ingesting. And supplements are drugs, although most people do not see them in that light. 5. If you give it to someone else, you will be held liable for any medical problems they may experience. In some jurisdictions it is illegal to do what you propose, because of the risk to other people. Antibiotics should be taken as infrequently as possible and only as prescribed by a medical doctor. They are most effective when used in this fashion. Irresponsible prescribing and use when they were first available has led to the development of many resistant strains of bacteria. Many people still demand them for every little ailment, even if they do no good.

Please don't.