According to an article by Innovative Men's Health
dated 20 March 2013 on the topic of Testosterone Therapy Side Effects vs Benefits Overview they say that although they have never seen the following side effects:
Nausea and/or vomiting; Headache; Skin color changes (this may happen if there are liver problems)
they do say that the above side effects are theoretically possible.
My husband has been on the testosterone gels for years and the doctor has never mentioned any haematocrit blood test. Also people who suffer from hypertension cannot donate any blood at all. A blood donation will not be accepted from someone suffering from hypertension even if they are on medication to control it.
Testosterone patches do not cause nausea. Nausea, however may be a symptom of a cardiac problem, and you should bring this to the attention of your physician immediately. Testosterone can cause cardiac irregularities.
It is easy to confuse nausea from a gastrointestinal problem with the onset of cardiac ischemia.
If you are over fifty or have a cardiac history, I would head for the ER. Mind you this is a worse case scenario.
The main side effect of the replacement is the possibility of stimulating growth of tumors, or the stimulation of red blood cell production. It is a good idea to have a hematocrit taken every three months. Some people on testosterone therapy are asked to donate blood every once in a while to reduce the hematocrit. The increase in blood cells increases the probability of a thrombosis, or clot.
You should have received an information note on the medication that you have been prescribed. If you have, then read that because it will tell you what the side effects are.
If there was not information note with your prescribed medication, then contact the doctor or the pharmacist about the diarrhea and nausea. You don't say which brand you have been prescribed nor the etc symptoms.
It may well be that this is a side effect of the testosterone and it does not suit you. Or it may just be coincidental that you have picked up a stomach bug.
My husband is on testosterone replacement, but has not complained of any symptoms. I complained on one brand because just the smell of it made me feel nauseous. So the doctor had to change the brand again.
Make an appointment and discuss this with your doctor.
Hope you get on OK.
Best wishes.