Brief Answer: Can be done. Maintain Hydation Detailed Answer: Dear Friend. Hi , I am Dr Anshul Varshney , I have read your query in detail , I understand your concern. Antibiotic excretion do occur in sweat. But it is not so significant that the effect of antibiotic will wean off. The only concern which should be kept in mind is that you are on Penicillin group of antibiotics and there excretion occurs mainly through kidney's. So , you should not get dehydrated during your workouts. If you are doing heavy workouts , just keep your self well hydrated. So , as far as antibiotics are concerned , there is no strong evidence that supports that one should not exercise while on antibiotics. However , if your primary condition for which you are on antibiotics requires rest , you should avoid exercises. Being on antibiotics is not a contraindication to exercise. This is my personal opinion based on details available here. If you still have any query you may please ask me. Stay Healthy. Dr Anshul Varshney , MD

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